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McCotmux, DifVlV Mlnttmu GEOLOGTCAI. SURVEY ' [memoir 98 I No- 81, Geological Sbmes Magnesite Deposits of Gren vilte District, Argenteuil County, Quebec BV M. E. Wilson* OTTAWA _^oyK8NiJENT Printing BuREAn 1017 No 85 View lookiPR wiitward fnirii rucky kiu>b, on lot 25, range X, rircnville townihip, showing the Laurenti ItAII I a I.aurcntian topography of the district, the southrrn portioii of Harrinnt.m flat, Kou.{i' rivor, and the Hell powr , 'int. View loQ Grenvitle township, showin CANADA DEPARTMENT OF MINES HoM. Ei. L. Patenaude, Minister; R. G. McConnbll, Deputy Ministeb. GEOLOGICAL SURVEY I MEMOIR 98] No. 81, Geological Series Magnesite Deposits of Grenville District, Argenteuil County, Quebec BY M. E. Wilson OTTAWA GOTEBKMENT PRINTING BURBAU 1917 No. 1685 CONTENTS. CHAPTER I. : Pagi lotroduction General itatement Magnesite Preparation of magnesite Uses of magnesite Foreign sources of supply Austria-Hungary Greece United States Other Canadian magnesite deposits. Production. 8 8 10 10 14 16 History of magnesite mining in Grenville district 17 » CHAPTER n. General geology *' General statement 19 Basal complex " General statement 1' Grenville series ^^ Buckingham series 20 Metamorphic pyroxenite 21 Granite-syenite gneiss 21 Late Pre-Cambrian intrusives 22 General statement 22 Diabase 22 Granite, quartz syenite, syenite, and quartz syenite porphyry 22 PaUeozoic 23 Pleistocene 23 Glacial 23 Marine clay and sand 24 CHAPTER HI. Magnesite deposits 25 Distribution and geological relationships 25 General character 25 Structure 26 Deformation 27 Mineralogy 28 Origin • •"* Determination of lime content of magnesite and magnesite-dolomite 34 Explanation of tables and outcrop maps 35 tt CHAPTER IV. Pace Deicripttons of properties 37 Lot 13, range I, Harrington township, Dobbie mine 37 Lot 18, range XI, Grenvitle township, Shaw mine 38 Lot 15, range XI, Grenville township 41 Lot 15, range X, Grenville township 51 Lot 15, range IX, Grenville township, McPhee property 52 Lot 13, range IX, Grenvitle township 58 Lot 16, range IX, Grenville township 59 Lot 11, range VIII, N. Grenville township, Campbell properly 59 Lot 12, range VIII, N. Grenville township 59 Lot 1 1 , range VIII, S. Grenville township 60 Lot 12, range VIII, S. Grenville township 60 Lot 9, range XI, augmentation of Grenville 60 Lot 21, range I, Harrington township 61 Lot 7, range X, Grenville township 61 CHAPTER V. Summary and conclusions 62 Illustrations. Map 1675 Diagram showing magnesite deposits, lot 15, range XI, Grenville township, Argenteuil county in pocket 1674 Diagram showing magnesite deposits, lot 15, ranges IX and X, Grenville township, Argenteuil county " 1679 Diagram showing magnesite outcrops, Grenville township, Argen- teuil county " Plate I. View looking westward from rocky knob on lot 25, range X, Grenville township, showing the Laurentian topography of the district Frontbpiece II. Weathered surface of crumpled sillimanite-garnet gneiss and quartz- ite, lot 22, range I, Wentworth township 65 III. Banded crystalline limestone, exposed in bed of West river, lot 20, range I, Wentworth township 67 IV. Knob of crystalline limestone containing nodular inclusions of peg- matite and pyroxene syenite, occurring east of the Scotch road, lot 18, range IX, Grenville township 69 V. Granite gneiss interbanded with and intruding pyroxenic gneiss of the Buckingham series 71 VI. Weathered surf ice of raagnesite-dolomite, lot 15, range IX, Grenville township 73 VII. A. Calcined Grenville magnesite-dolomite 75 B. Calcined Grenville magnesite, showing inclusions of dolomite . 75 VIII. A. Calcined Grenville magnesite-dolomite 77 B. Grenville magnesite-dolomite calcined in a reducing at- mosphere 77 iX. Disseminated grains of serpentinized diopside forming parallel bands in Grenville crystalline limestone, Buckingham, Quebec 79 X. Kiln and mill. North American Magnesite Company, on the McPhee property, lot IS, range IX, Grenville township 81 Ill Page Plate XI. No. 3 pit, Scottuh Canadian Magneaite Company 83 Figtire 1. Location of Grenville area 2 2. Diagrammatic tection acroea south (ace of pit in magneaite deposit, lot 18, range XI, Grenville townahip 39 0h Magnesite Deposits of Grenville District, Argenteuii County, Quebec. CHAPTER I. INTRODUCTION. GENERAL STATEMENT. As a consequence of the present war the supplies of numerous mineral materials formerly imported into Canada and United States from abroad have been partly or completely cut off and for this reason special attention has b«en directed to the investigation of deposits of these minerals occurring on this continent. Among the minerals of this class one of the most important is the magnesium carbonate, magnesite, the world's supply of which was formerly derived almost entirely from deposits in Austria-Hungary and Greece. The restricted importation of this material, especially during a period of unprecedented activity in the metallurgical industries, has brought about a complete transformation in the market conditions in America for magnesite. The almost complete dependence of the American consumer on foreign sources of supply of magnesite prior to the war and the readjust- ment which is now taking place is indicated by the statistics of import- ation and domestic production in the table on pages 12 and 16. In 1913, the year preceding the outbreak of war, 172,591 short tons of calcined ms^esite and 22,872 tons of crude magnesite were consumed in United States, of which (only 9,632 tons of crude) less than 3 per cent was produced at home; whereas in 1915 the total consumption of magnesite in United States was 26,574 short tons of calcined and 80,267 short tons of crude, of which approximately 23 per cent was domestic production. Likewise, the production of magnesite in Canada ina^ased from 515 tons valued at $3,335 in 1913 to 55,413 tons having a value of $563,829 in 1916. Up to the present time (March, 1917) the increase in the domestic production in North America has been derived almost entirely from Canadian deposits situated a few miles north of Ottawa river in the Grenville district, Quebec, and from scattered occurrences in the state of California in United States. Though the Canadian magnesite contains more lime than the California magnesite and in that respect is of inferior quality, in every other respect it ha. many advantoae. over th« r-i; (2) The California deposits taken as a whoU ar* ^ i:^: j • •mall part of the magnesite needed in United States.* Figure 1. Location of Grenville area. ..•^..SS ^'""^ ^''^ principal manufactories consuming magnesite are «tuated m the eastern part of the continent and the fS rate Tr JLf^ °1' <^^"a Morianrath, L. C, BuU. / • GowUni, W.. "The meu." > Accordint to R. H. Yoimf u. '. Min. Ens.. No. 93, 1914, p. 23S1. the non-ferroiu mlnenlt," 1914, p. 10. >l Rout. H. J.. "Tbaderclopment of CaaullaD mamnitc," \nnual meeting. Can. MIn. Inat.. I9IT. Oxyehloridi or Scr*t Cenunt. A mixture of finely ground caustic calcined magnetite and magnesium chloride known aa oxychtoride or Sorel cement has been uied extendvely in recent years as saniury flooring, stucco, artificial marble, tile roofing, and other structural material, llie use of magnesite for this purpose is based on the fact that when wet with a solution of magnesium chloride of a certain concentration it sets as a hard vitreous cement. As a flooring, this material when properly mixed and laid is much superior to any other variety of cement. It can be coloured, takes a good polish, is waterproof and fireproof, and does not pulveriie to dust. Certain practical difficulties have been encountered, however, in procuring a raw material of uniform quality and in consequence the floors have not always been satisfactory. In practice it is generally customary to add certain materials such as wood, serpentine, talc, ground quartz, asbestos, and other substances to the mixture as filler, the resultant mixture being sold under a great variety of trade names such as artificial marble, asbestolith, asbestos floors, compolite, compostone, kellastone marbeloid, monolith, petrified wood, sanitary f*~or8, scagliola, stonewood, tileine, and velvetile. Manufacture of Wood Pulp by the Sulphite Process. Considerable amounts of magnesite are consumed in the manufacture of chemically prepared wood pulp, for use in the manufacture of paper. The pre- paratbn of wood pulp by this process consists in boiling the wood with a chemical reagent which will serve as a disintegrating agent. For this purpose either sulphurous acid or calcium or magnesium bisulphite are generally used. The magnesium bisulphite is generally preferred, how- ever, because of its greater stability and because of its greater solvent action on T.-ood resins. Manufacture of Carbon Dioxide. Considerable quantities of carbon dioxide were formeriy manufactured from magnesite, but limestone or coke is now generally used for this purpose. Carbon dioxide is manu- factured from crude magnesite by calcination and the recovery, puri- fication, and compression of the carbon dioxide gas evolved, the residual caustic magnesia being sold as a by-product. In practice it has been found, however, that in order to obtain the most efficient results in the manufacture of carbon dioxide the crude magnesite has to be calcined at a lo*rer temperature than that required to produce caustic calcined magnesite, that is, the residue contained too much carbon dioxide. On this account the use of magnesite for the manufacture of carbon dioxide is decreasing. Since the calcination of the crude magnesite effects a reduction in weight of nearly 50 per cent it has been generally found t" be more economical to calcine the magnesite at the mine and redM^e the cost of shipment, and usually no attempt is made to save the carbon dioxide in this operation. I •J "CM Water" Paint. BecauM of iu refractory qualities caustic calcined magnetite ia now uied in the manufacture of fireproof paint. For thia purpose a finely ground mixture of caustic calcined magncsite and magnesium chloride is prepared and is mixed w:th cold water for r"!^lication. Metallic Maitusium. Prior to the war the world's supply of metallic magnesium was largely produced in Germany where it was manufactured from m''~nesium salts obtained from the salt deposits at Stassfurt. It is now being produced in considerable quantities in France, England, United States, and Canada. Owing to the increased demand for the metal for military purposes and restricted importation the price of magnesium rose rapidly in United States after the outbreak of the war from tl-40 per pound to $5 to SLO per pound in 1914. During 1915 the prevailing price in New York was 15 per pound, but it has since fallen considerably, present quotat'ons being S3.50. The importation of magnesium into United States before the war according to the statistics of the Department of Trade and Commerce was 38,000 pounds per annum. This, according to Dr. W. M. Grosvenor,' was considerably less than the actual consumption, the magnesium being imported by some manufacturers under other names. The normal consumption in United States for domestic purposes is stated by Dr. Grosvenor to be 50,000 pounds per year, an amount approximately equivalent to 90,000 tons of crude magnesite. The total production of i..«;tallic magnesium in United States in 1915 was 87,500 pounds valued at about $440,000.* The usual process employed in Germany for the manufacture of magnesium was by the electrolysis of the fused double chloride MgCU Kcl. It is said that it can also be made by the following processes: the reduction of magnesium chloride with metallic sodium; the reduction of the oxide with carbon; the electrolysis of magnesia; the reduction of fused chloride with aluminum; the reduction oi the oxide or carbonate to slag forming residues; and other processes.* In Canada, metallic magnesium is now being manufactured elec- trolytically from magnesite by the Shawinigan Electrometals Comjyany at Shawinigan,* Quebec. The details of the process employed have not been published, but Canadian magnesite is being employed' as the crude material. The principal use of metallic magnesium GroBvcnor, Dr. W. M.. Mftal and Chrm. Enii., vol. 14. I<<1(>. p. J6J. the province of Styria (Steigermark) in Austria and to northwestern Hungary. In the first locality the most important deposits occur near the town of Veitsch. The largest fleposits in northwestern Hur,j,ary lie between the towns of Jolsva and Nyusta. The magnesitc found in Austria-Hungary is mainly a grey to drab variety, occurring in association with talc, quartz, dolomite, calcite, pyrite, and other minerals as enormous lenticular masses several hundred feet in diameter. The larger part of the impurities contained in the magnesite are removed in practice by cobbing at the mine and by sorting after the product has been calcined; so that except for the iron which it contains a magnesite of a fair degree of purity is produced. It is said that the Austro-Hungarian magnesite, owing to the iron which it contains, is more readily reduced to the dead burned state and that the iron oxide contained in the product serves as a binder in making furnace linings and in the manufacture of magnesite brick, and that on this account, except where a more highly refractory material is required, Austro- Hungarian magnesite is preferred.' Analyses follow: Chemical Analyses of Typical Austro-llungarian Magnesite. I II III IV V SiO, 0-45 0-76 5-83 0-74 0-74- 0-76 Al.O, trace 0-14 0-48 0-39 0-39- 0-27 Ff,0, 3-65 S-72 1-54 3-27 3-27- 3-43 Mn,0, trace 0-94 ("uO 097 0-32 4-52 0-20 1-20- 0-90 MgO 4,? -82 43-06 .19-54 44-80 44- 80-15 -(K) CO, 50-44 49-81 47-99 50-10 50-10-50-20 Total 99-33 100-25 99-90 99-50 I. II. III. IV. V. Veitsch, Fortschritte der Min., Krist. unci Pet., vol. 4, 1914, p. 29. IJrItenau, " " " " " Dientcn, F.icheiter C. F., Jahrb. d.k.k. geol. R.A., 1907, p. 927. lolsva, Fortschritte der Min., Krist., und Pet., vol. 4, 1914, p. 32. Nyustya, Bull. 355, U.S.G.S., 19C8, p. 56. Because the Austro-Hungarian magnesite deposits are closely associated with Palajozoic marine sediments it was formerly assumed that the magnesite was of sedimentary origin; but the closer study of the deposits during recent years has lead to the conclusion that they are in reality metamorphic deposits formed by the action on Palaeozoic lime- stone' of magnesium carbonate solutions, derived from basic intrusives. ■ Morganroth, L. C, "The occurrence, preparation, and uie of magneaite." Bull. Am. Intt. Mia. Eng., 1914. No. 93. pp. JJ45-23S2. ' Rumpf, J., "Oeber kriitallisierte magneiite aua den nordtistlichen Alpen, Tachermak'i Mineralogiwhc Mitt.. 1«73. p. 263. Weinschenk E.. GruniuRe der CrtMtteinskunde. Freiberg vol. 2, I90.S. p. 315. RldUch, Karl A.. Fortschritte der Min. Krist. und Pet. vol. 4, 1914. pp. 9-42. Kern, A.. Der Magnetit und Seine techniicbe Verwertung, Glttchauf, 1912. pp. 271-275. 10 The quantity of calcined magnesite exported from Austria-Hungary during the years 1909 to 1913 was as follows: Metric tons. IQOQ 125,666 IqH) 182,911 9 , '47'*«' Q 2 171,196 \9\i.y.... 200,947 Greece. Magnesite is found at a number of localities in Greece, but the important deposits are situated on the island of Euboea, where it occurs associated with serpentine in numerous masses and veins up to 50 feet or more in width and several hundred feet in length. The magne- site is of the massive variety and contains the usual associated quartz, dolomite, and other impurities. The larger part of these are cobbed out in mining the material, however, so that a product of exceptional purity is produced. Analyses follow: Analyses of Typical Grecian Magnesite. SiO,. . . MO,... FojOi . CaO MrO.. CO2 . Total 0-20 0-20' 0-20 0-51 4711 51-77 98-99 0-90 0-86 1-53 45-45 51-26 100-00 0-38 fO-15 \0-08 1-68 46-09 51-51 1-63 0-17 119 1-44 45-75 49-88 99-89 100-06 Since the Euboean magnesite daposits are all situated in close proxi- mity to the seashore, under normal conditions Grecian magnesite has the advantage of cheap water transportation to the^ principal magnesite markets of the world. P' t~ V — « 3 «♦ - - - OvM**> W)"* 1 ^ m ■* Ov O*^ f*5 t^^f xes^ xin s ^. OC**) o o" -Tw)* —4 sss m — « — u ioo> 3 «» - - - "rt r* 00 > o_ ^ 2 l^»0«N p. « c.«g 'M ^ I^f^ VO-" Ot^Ov ■5x0 (NCSf^ .OfS u <»)«~l~ mm 3 •»0(M-" ss ? -" •* r*^ o #< »o tt^Ov Ot-. 0>«iO j:S a> «00 1« « (M gs > v^ ^ Ov Ou^tn trt-^ 0) ^ (sr^ t^t^ B o>_ °^- O <-» tN •^^^-v edicinal) medicina psom-sal i'- ■c : a : E— (d C- u^ c . .Icined rbonat Iphate nestle ■s ; C u §C^^.§du ^ ^ i 13 14 OTHER CANADIAN HAGNESITE DEPOSITS. The occurrence of magnesite in numerous widely scattered localities in Canada is recorded in the reports of the Canadian Geological Survey, but the meagre information given with regard to most of the occurrences indicates that most of the deposits are of too limited extent or are too remote to be of commercial importance. In New Brunswick a vein of magnesite several feet wide is said to occur in grey chloritic schist on the bay shore of St. John county near West Beach.' In Quebec, magnesite is found (in addition to the Grenville district) associated with serpentine and talc in Sutton and Bolton townships, Brome county. One of these deposits on lot 17, range IX, Bolton township,'' is stated to be 20 yards wide. In Ontario, a blue ferruginous magnesite occurs in association with finely crystalline pyrite on Lac des Mille Lacs,' Algoma district. In British Columbia, the presence of magnesite is recorded at lUecillewaet in the Kootenay district,* on Germansen creek in the Omineca district', at 108-Mile House on the Caribou road in the Lillooet district,' and in the vicinity of the town of Atlii. in the Atlin Mining Division.' In Yukon Territory ferruginous magnesite was observed by Mr. R. G. McConnell on Big Salmon river, a tributary of the Lewes river, and on Yukon river about Ij miles above the outlet of Indian river. In the first mentioned locality the magnesite occurred in a band 50 feet thick in association with dark, partly altered slates, greenish schists, and serpentine.' Magnesite is also reported to occur in sedimentary beds on the Yukon-Alaska boundary north of Porcupine river.' In the Atlin Mining Division of British Columbia both magnesite and hydromagnesite were observed by Gwillim, but the extensive masses of hydromagnesite occurring in the vicinity of the town of Atlin are the most imp)ortant. These deposits are superficial beds of fine powdery white hydromagnesite having a thickness ranging from 8 feet to 6 feet and covering areas up to 18 acres in extent.'" Analyses of this material made by Mr. N. L. Turner of the Mines Branch gave the following results: > Bailey, L. W.. and Matthews. G. F.. "Preliminary report on the geology of southwestern New Bruns- wick," Geol. Surv.. Can., Rcpt. of Piog., 1870-1871. p. 237. » Geology of Canada, 1863, p. 457. Geol. Surv., Can., Ann. Rept. new ser., vol. IX, 1896. p. 95 S. • Geol. Surv., Cai., Ann. Rept., new ser., vol. I, 1889, pt. M.. p. 22, • Geol. Surv., Can.. Ann. Rept.. new ser.. vol. IX, 18V6, p. 96S. , • McConnell, R. G., "Report on an exploratior of the Findley and Omineca rivers." Geol. Surv.. Can.. Ann. Rept., vol. VII, 1894, p. 25. •Geol. Surv.. Can., Ann. Rept., vol. II. 1898, p. 10. ' GwilHm. J. C, Geol. Surv., Can., Ann. Rept., vol. XII. 1899, p. 72A and p. 46B. •Geol. Surv., Can., Ann. Rept., vol. II, 1898, pp. 16-17R. •Caimes, D. D., Geol. Surv., Can.. Sum. Rept., 1911, p. 33. '• Young, G. A., Geol, Surv., Can., Sum. Rept., 1915, pp. 50-61. 15 Analyses of HydromagnesiU from Atlin, B.C. SiO, Al,0, Fe,0, KeO CaO MrO CO, H.O + Total H,0 - 1-86 0-67 . 015 0-60 2()4 41 13 18 02 l()()-45 192 0-90 010 009 45 0-82 42-35 36- 10 18-95 99.76 0-54 0-17 0-11 0-64 O-hS 42-19 ihV 19-05 99-55 1-35 0-74 35 0-15 0-()(> 0-32 42 ■S5 36-35 19-10 l(HI-52 1-21 96 0-23 012 0-53 0-16 43-04 36-21 19- 20 l(Kt-51 9-34 A number of hypotheses to account for the origin of the hydro- magnesite have been proposed by those who have studied the deposits in the field. Gwillim suggested that the material has been deposited from springs, an hypothesis which seemed to be supported by the results of analyses of water from the springs of the district, sin e these were found to include considerable magnesia. Robertson', who examined the deposits in 1904, concluded, however, that the hydromagnesite was a product resulting from the weathering of magnesia-rich rocks directly underlying the deposits. Young', on the other hand, pointed out that the deposits have not the tuflfaceous structure of spring deposits and do not rest on magnesia-rich rocks but on soil, and concluded, therefore, that there are valid objections to the hypotheses of Gwillim and Robertson, and suggested that the hydromagnesite represents material deposited on the bottoms of ponds which have disappeared since the deposition occurred. It is estimated by Young that two groups of deposits occurring in the outskirts of the town of Atlin contain approximately 180,000 tons of hydromagnesite. RecentlyC. W. Drysdale' has discovered magnesite near the northwest end of Liza lake in Bridge River district, Lillooet mining division, British Columbia. The magnesite found in this locality is a buflf yellow massive variety occurring as masses and veins in serjjentinized magnesian rocks and is thus similar in character and origin to the deposits of California. I Robertson. W. F., Rept. of Minister of Mines. B.C.. J91S. pp. 82-83. = Geol. Surv.. Can.. Sum. Rept., 1915. pp. 55-61. ' Gcol. Surv., Can., Sum. Rept., 1915, p. 83, and 1916. p. 48. 16 Analyses of the magnesite made by Mr. N. L. Turner of the Mines Branch resulted as follows: Analytts of MatnesiUfrom Bridt* RiMr, B.C The outcrop from which the above representative samples were taken measured 52 feet by 48 feet, indicating that the deposits are extensive. They are situated at a distance of over 30 miles from the nearest point on the Pacific and Great North-Eastern railway, however, and are, therefore, too remote to be profitably mined at present. A deposit of magnesite has recently been discovered near Orangedale, Inverness county. Cape Breton island. The magnesite is a brown crystalline variety having the following composition: SiO 0-30 AliOb 101 Fe,0, 1-71 Total, P6-67 MgCO, 90-80 CaCO, 2-85 When visited by A. O. Hayes of the Geological Survey in the summer of 1916 an outcrop about 100 square feet in area was exposed, protruding through sand and clay. Since that time 30 tons of magnesite have been mined from the deposit by the Nova Scotia Steel and Coal Company which has acquired possession of the property. PRODUCTION. The production of magnesite in Canada since the year 1908 as compiled by the statistical division of the Department of Mines is as follows: Year Tons. Value. $ 1908 120 840 1909 330 2,508 1910 ' 323 2,160 1911 ... 991 5,531 1912 1,714 0,645 1913 SIS 3,335 1914 358 2,240 1915 14,779 126,584 1916 55,413 563,829 17 nes rere are the ver, ale, jwn mer ling •een any I as s is HISTOKY OF MAGNESITE MINING IN GRENVILLE DISTRICT. In the month of June 1900, Reverend W. P. Boshart in the course of a visit to Mr. Donald McPhee, lot IS, range IX, Grenville township, observed a boulder lying a short distance from Mr. McPhee's house which had a whiter and more glistening appearance than the ordinary crystalline limestone of the district. He sent a specimen of the material to Mr. W. B. McAllister of Ottawa, who took the sample to the Geological Survey where it was determined to be magnesite. Learning that magnesite was of commercial value, a search for the mineral in place was undertaken by Messrs. McAllister and Boshart with the result that outcrops and boulders of similar material were found in numerous localities in the district. Later in the season Mr. R. L. Broadbent of the Geological Survey visited these localities and collected samples which were analysed by Mr. F. G. Wait of the section of chemistry and mineralogy of the Geological Survey. The results of these analyses were published in the report of the Geological Survey for JOO.' Following the discovery of the magnesite, Messrs. McAllister and Boshart procured options on a large part of the territory in which the magnesite was known to occur, and made trial shipments of the material to consumers of magnesite, but the prices offered were too low for profit- able operation, and no further attempts were made to market the material until the year 1907, when Mr. T. J. Walters purchased the mining rights for the north half of lot 18, range XI, Grenville township, from the Government and organized the Canadian Magnesite Company to operate the property. Later this company also acquired the mining rights for lot 15, range IX, Grenville, from Mr. McPhee, and erected a 10-ton keystone kiln on this lot for the purpose of calcining the magnesite at the mine, thus reducing the cost of haulage to the railway at Calumet. 11 miles distant. Mining operations were continued by the Canadian Magnesite Company on lot IS, range IX, in a small way, until the year 1914, when the property of the Canadian Magnesite Company was taken over by the North American Magnesite Company. Since that time mining has been actively prosecuted, both crude and calcined magnesite being shipped. In 191S Mr. S. Melkman of Montreal organized the Scottish Canad- ian Magnesite Company to mine magnesite on lots IS, ranges X and XI, Grenville township, under contract with the Grenville Lumber Company, to which these properties belonged. Magnesite mining was commenced in the month of August, 1915, by this company and has been continued up to the present. Since that time the Scottish Canadian Magnesite Company has acquired the controlling interest in the Grenville Lumber ' Gtol. Sor.. Can.. Ann. Kept., vol. XIII. 19O0. pt. R., pp. 14-19 18 Company and ha. constructed a light railway 14 mile, in length con- ncrting their depo.it. with the Canadian Pacific railway at a pomt about 2 miles east of Grenville station. In October 1916. Mr. A. Lannigan and Mr. J. Milway of ( alumet discovered a deposit of magnesitc on lot U. range 1, Harrmgton town- S which has^nce been acquired and operated by the International Magnesitc- Company of Montreal. Some development work on magnesitc prospects has al^, been performed by Messrs. Boshart and Fitzsimmons during the past year and Tfew tons of magnesitc shippeliutied. (2) Intrutive iKneous rocks of late Pre-Cambrian age. (3) Approximately Hat-lying sandstone shale and sandstone of early Pal.iiizoic age. (4) 1,'nconsolidated gravel, sand, and clay of I'Uistucene and kccent age. Arranged in tabular form the succession of formations in the district in detail is as follows: Table of Formaltons. Quaternary Champlain Marine clay and siintl. (ilacial Boulder clay, gravel, and sand Palaeozoic Chazy Sandstone, shale, and lime- stone. Beekmantown I imeston*' I*otbdam . . Sandstone Late Pre-Cambrian . . Granite, quartz syenitf., syen- ite. Dialiasc. Early Pre-Cambrian. . Granite-syenite gneiss. ' Metaniorphic pyroxenite. Buckingham (igneous) series. . . I'yroxcne syenite. Pyroxene diorite. Pyroxene gabbro. Pyroxenite. Grenville series Quartzite, garnet-sillimanite gneiss, ci _ talline limestone. BASAL COMPLEX. General Statement. The basal con;plex, the oldest of the four great groups into which the rocks of the Grenville district have been subdivided, is composed of a heterogeneous assemblage of sedimentary and igneous rock types which, though not all coiitemporaneom In age, have all been partly or completely trantformcd to a crystolline or foliated condition ai a re«ult of the regional meUmorphi«m to which they have been iubjected. In thit respect they are strikingly in contrast with the rocka that succeed them in that the latter are not metamorphosed and retain all the char- acteristics by which they were oriijinally distinguished. If classified merely on the basis of age. the rocks of the complex must be regarded as belonging to only three groups: (I) a group of rccrysullized marine sediments cc stituting the Grenville series; (2) a group of igneous pyroxenic rocks of intermediate composition intruding the rocks of group 1. constituting the Buckingham series; and (3) batholithic masses of granite and syenite gneisses intrusive into the rocks of groups 1 and 2. jUt the metamorphic action of the pyroxene gneisses of group 2 on the limestone member of the Grenville series has transformed considerable mawes of this rock into diopside and related minerals forming a fourth common rock type generally known as "pyroxcnite." The rocks of the Grenville series, being the least resisUnt to erosive agencies of all the rocks in the district are generally found to underlie the valleys, whereas the granite gneisses which are least easily eroded, form all the prominent hills (Plate I). Grenville Series. The oldest rocks recognized to be present in the Grenville district belong to what is generally known as the Grenville series. It is believed that the rocks of this series were originally laid down as alternating beds of shale, sandstone, and limestone, but, owing to the intense meta- morphism to which they have been subjected, the shale has been recry- stallized to sillimanite-garnet gneiss (Plate II), the sandstone to > treous quartz, and the limestone to crystalline limestone (Plates III and IV). The reasons for this conclusion are: (1) chemical analyses of the silli- manite-garnet gneiss member of the series show that this rock has in every detail the chemical composition of a shale and thus the three rock types, sillimanite-garnet gneiss, quartzite, and crystalline limestone have respectively the composition of the three dominant members of marine sedimentary series of the well sorted types, and (2) these rocks occur interstratified with one another in a manner similar in every respect to the way normal marine sedimentary deposits usually occur. Buckingham Series. The Buckingham series is a group of igneous pyroxenic rocks found widely distributed throughout the Pre-Cambrian of southern Quebec and eastern Ontario. In the district where the series was originally des- 21 cribed memben of the lerieit occur ratiKing in componitiun from pyroxene j^ranite to peridotite; but in the Grenvillc district only pyroxene syenite, pyroxene diorite, pyroxene gabbro, and pyroxenite were ojjscrved. These have been intruded in the (ircnvitle scries partly as thin bands injected between the beds or alon^ the plnnes of foliation and partly an large lenticular bosses. Since thiir intru!>'. the grani'i; syenite indicating that in part, at least, they are includeil ;'.<:;:'■ :>';.l olJer in age than the granite syenite. Though the (Irenville stock is not found in actual contact with either the diabase dykes or the PaUeozoic sediments occurring in the district, it is probable, as was concluded by Sir William Logan, who studied the mass in 1853, that it is younger than the former and older than the latter; for the diabase dykes, although abundant throughout other portions of the region, have nowhere been observed to penetrate the stock, whereas dykes similar in composition to the granite syenite of the stock have not been obst^rved to intrude the Palspozoic sediments which outcrop in c!f)se proximity to the stock on the south. It would seem probable, therefore, that the Grenville stock is very late Pre- ("ambrian in age. PAL.EOZOIC. That portion of the Grenville district which lies adjacent to Ottawa river and south of the Laurentian escarpment is underlain by approxi- mately flat-lying beds of Paiax)zoic shale, sandstone, and limestone, which protrude here and there as ledges in the stream bottoms or as low east-west trending escarpments. The formations represented by these .sediments named in ascending order include the Potsdam, the Beek- mantown, and the Chazy. PLEISTOCENE. Glacial. In common with the whole territory formerly covered by the Labra- dorean continental glaciers, the bedrock surface of this region is covered by an irregular mantle of glacial debris. This consists in the main of scattered boulders and irregular knobs or ridges of gravel and sand, in many parts of which deep undrained depressions occur. 24 Marine Clay and Sand. Throughout all the lower portions of the Grenville district the glacial and older formations are overlain by stratified clay and sand which contain marine shells and which form extensive flats (Plate I) m the depressions within the Laurentian plateau. These marine deposits are found up to elevations of 735 feet above sea-level.' The character of these deposits varies considerably from point to point, but m the main, the clay beds predominate at the bottom and the sand at the top. In the vicinity of Ottawa river, the sand occurs in extensive areas, in place' with a typical desert-like duned surface. Ticcording to d«».tiont on H.wke.b«y theet piihlirt«d by the D*p«tment of MiUti. wd DrffOCT- 25 CHAPTER III. MAGNESITE DEPOSITS. DISTRIBUTION AND GEOLOGICAL RELATIONSHIPS. The deposits of magnesite so far discovered in the Grenville district are found in four principal localities; the north end of lot 15, range IX. the south end of lot 15, range XI, and the north end of lot 18, range XI, Grenville township; and lot 13, range I, Harrington township. At all of these points, the magnesite occurs associated with ser- pentine, dolomite, and other minerals in lenticular outcrops protruding through the marine clay and sand which, in this district, as everywhere in the Laurentian highlands adjoining the lower Ottawa and lower St. Lawrence, occupies the bottoms of the major valleys. On lot 15, range IX, Grenville township, the magnesite deposit is adjoined on the west by Grenville quartzite, and on the east at a distance of about 400 feet, outcrops of pyroxenic syenite belonging to the Buckingham series occur. On lot 15, range XI, Grenville township, the conditions are very similar to those on lot IS, range IX, Grenville quartzite occurring on the west and pyroxenic gneiss on the east, but between the pyroxenic gneiss and the magnesite several outcrops of metamorphic pyroxenite are present. On the Shaw property, lot 18, range XI, Grenville township, garnet gneiss belonging to the Grenville series occurs to the east of the deposit, meta- morphic pyroxenite to the south, and crystalline limestone to the north- west. On lot 13, range I, H "^on township, the adjoining outcrops consist of pyroxenic gneiss, c ■" limestone, and garnet gneiss. In general, therefore, it may be s, .t the magnesite in all of its occur- rences is found in association with the metamorphosed group of sedi- ments, viz., crystalline limestone, garnet gneiss, and quartzite, composing the Grenville series, and that in three localities it is found in close proximity to outcrops of the pyroxenic rocks o' the Buckingham series. GENERAL CHARACTER. The magnesite found in the Grenville district is a glistening cream white to milk white or grey materia' irring in extensive masses associ- ated with bands or lenses of dark green to light yellow serpentine. Ser- pentine also occurs disseminated in the magnesite in places and the magnesite nearly everywhere contains more or less included dolomite. Moreover, since dolomite (CaCO, MgCOj) contains 30 per cent of lime, the magnesite generally contains a certain amount of lime also, the 26 percentage present varying in proportion to the amount of dolomite which the magnesite contains. In a few localities the dolomite mcluded in the magnesite is more coarsely crystallized, and is whiter m colour than the surrounding material, and can be distinguished m this way, but, throughout the great mass of the deposits, magnesite and dolomite are so similar in appearance that the presence of dolomite is difficult to The intimate manner in which dolomite is disseminated through the magnesite is made evident in several ways. Where the magnesite outcrop has been exposed to atmosvheric agencies, dolomite, being more soluble than the magnesite, dissolves away more readily, so that the weathered surface presents an irregularly pitted appearance, the magnesite forming the prominences and the dolomite occupying the bottoms of the depressions. This feature is well exhibited in Plate VI . The presence of dolomite in the magnesite can also be detected by treating the mixture with cold concentrated hydrochloric acid, effervescence occurring where the dolomite is present. The relationship of the dolomite to the magne- site can best be observed in the material after it has been calcined in a kiln or furnace without access of air (deoxidizing atmosphere), t.ie dol- omite assuming a white and the magnesite a pink colour as a resuk of tl.is operation. A number of specimens of magnesite colle:ted by the writer were sawn .md calcined in the ceramic laboratory of the Mines Br inch of the Department of Mines by Mr. H. Frechette (Plates VII and VIII). It will be observed that in these specimens the dolomitic portions appear to be included in the magnesite and possess a most irregular outline. STRUCTURE. In highly crystalline metamorphosed rocks, such as comprise the Grenville magnesite deposits, structural features are not everywhere apparent; but, in some of the deposits, parallel planes of parting, banding, and other features are conspicuous. The outcrops in which the magnesite is found are all elongated in a direction approximately parallel to the trend of the bedding of the quartzite and garnet gneiss belonging to the Gren- ville series which outcrop in the vicinity of the deposits; likewise, within the deposit .he elongation of the masses of serpentine, the strike of the planes of parting, and the banding, which characterize the magnesite, all trend in a direction parallel to the longer direction of the outcrop and the strike of the adjoining Grenville sediments. The banded structure generally present in the magnesite arises in part from variations in the colour of the magnesi.e and in part from variations in the proportion of disseminated serpentine which it contains. The width of the successive bands is exceedingly variable ranging from leas than an inch to one foot, although on the whole the wider bands are 27 most common. It was observed that the proportion of serpentine in the bands changed in places when followed along the strike of the bands and, that at some points, the banded magnesite passed by a gradual increase in the proportion of disseminated serpentine into solid masses of serpentine. The most conspicuous structural feature exhibited by the magnesite deposits is their prevailing lenticular form. Along the eastern margin of the main pit on the McPhee property (lot IS, range IX, Grenville township) there is a northeasterly trending lens (sample area 97, Map 1679) of medium to coarse-grained, white dolomite, 60 feet long ind 10 feet wide; 50 feet to the south of this, lens there is a parallel trend- ing lens (sample area 114, Map 1679) of coarse grey dolomite, 100 feet long and 20 feet wide, in which pyrite and zinc blende are dissemin- ated. Both of these lenses apparently lie on the eastern flank of a still larger lens; for, their axial planes, as well as the banding in the adjoining magnesite, dip 75 degrees towards the southeast, whereas SO feet westward the dip of the banding and planes of parting in the magnesite are 7S degrees towards the northwest. A still more striking example of the lenticular form is that exposed m the west face of the northern pit on the same property. At the south end of this face the banding and parallel planes of parting in the magnesite have approxi- mately an east-northeast strike and a dip gradually curving downward towards the north-northwest. At the north end of the face 80 feet farther to the north the strike is approximately east and the dip curves downward toward the south at the top of the face but reversef back to the northward at the bottom. On the face of this pit, therefore, there is apparently exhibited a cross section of the lower portion of a large distorted lens. DEFORMATION. That the magnesite deposits have been intensely faulted, crumpled, and otherwise deformed is indicated by numerous slickensided surfaces, dislocations in the banding along planes of fracture, and variations in the strike and dip of the banding and planes of parting. One of the most striking evidences of deformation in the deposits was observed near the west side of the pit on No. 3 outcrop, lot 15, range XI, Grenville town- ship. At this point there is a dyke of biotite-pyroxene syenite, 6 inches in width, which has been crumpled into a closely compressed anticline. The magnesite exposed in the southern pit on No. 2 outcrop on the same property was also observed to be granulated in places — ^another evidence of intens leformation. It is probable that the le- ' -cular structure so common in the magnesite deposits is also the result ot deformation, since the banding in the magnesite adjoining the lenses everywhere conforms 2S to the margin of the lens. This feature is exceptionally well shown -.here the magnesite adjoins a crumpled lens of serpentme m sample areas Nos. 41 and 42. on the No. 1 outcrop on the Scottish Canadian property (Map 1679). MINERALOGY. The minerals observed to be present in the magnesite deposits, named in the order of their abundance, are as follows: magnesite. sfT- pentine, dolomite, diopside. phlogopite, quartz, talc, pyrUe, spha ente. magnetite, and graphite. The character and mode of occurrence of each of these are briefly described in the following sections. Magnesite (MgCO,; magnesium 47-6, carbon dioxide 52-4 per cent). Magnesite or magnesium carbonate as found in the Grenville district is a glistening cream white, snow white, milk white, or grey, fine-grained material having a specific gravity of 3 00 and a hardness of 3-5. The general character and mode of occurrence of the mineral have been described in previous sections. Serpentine ^3MgC. 2SiO,.2H,0: magnesia 43, stltca 44- 1. water 12-9 per cent) The serpentine found in the magnesite deposits occurs partly in masses or bands of various sizes up to several hundred feet in length and SO feet inwidth and partly as round grainsdisseminated through the magnesite or magnesite-dolomite. It may be dark green or almost black, emerald green, blue green, yellow green, yellowish brown or wax yellow in colour, is exceedingly fine-grained, and possesses a waxy lustre. In the larger masses it commonly contains considerable finely disseminated amber brown mica. .• •. Dolomite {CaCO^MgCO,: magnesia 21-7, limt 30-4, carbon dtoxtde 47 ■ 9 per cent) . The dolomite associated with the Grenville magnesite oc- curs partly as small grains or aggregates of grains intimately disseniinat- ed through the magnesite, and partly as large irregular masses or .enses included in the magnesite. Conesponding to these two modes of occur- rence there is a marked difference in the physical character of the mineral : for while the disseminated dolomite is generally fine-grained and glisten- ing and similar in appearance to the magnesite, the large masses are coarsely crystallized with a well developed rhombohedral cleavage. Diopside {CaMg{SiO,W lime 25-9, magnesia 18-5, silica 55-6 per cent) Extensive masses of the variety of pyroxene known as diopside are included in the magnesite deposits in a number of localities, especially near the contact of the magnesite with the Grenville quartzite which adjoins the deposits in places. The mineral as found in these masses is not strikingly different in appearance from the magnesite. It can be distinguished, however, by its somewhat greater specific gravity, rect- angular cleavage, vitreous lustre, light pale green colour, and sub- translucency. 29 Phlogopite {composition variable approximately, silica 40, alumina 17, magnesia 27, potash 11, fluorine 2, water 3 per cent). Phlogopite, or amber mica, as far as was observed, is confined entirely to the large masses of serpentine in which it occurs in the form of finely dissemin- ated flakes. It is a typical light amber variety quite similar in every respect to the phlogopite found in association with the contact pyroxe- nite in other parts of the same region. Quartz (.SiOt). Masses of quartz were observed to be present in the magnesite deposits, at the north end of No. 1 outcrop on lot IS, range XI, Grenville; at the southwest end of the main pit on the McPhee property; and on the northwest margin of the pit opened by Messrs. Fitzsimmons and Boshart at the south end of lot 16, range IX, in Gren- ville township. It is (X)ssible that ail of these occurrences are merely beds or masses of Grenville quartzite, since extensive outcrops of this rock adjoin the deposits. Talc {3MgO.4SiOi.HiO: magnesia 31-7, silica 63-5, water 4-8 per cent). The talc found in associaton with the magnesite deposits is char cterized by the waxy lustre and light greenish grey colour which usually characterize that mineral. It occurs chiefly with serpentine, filling fractures in the diopside masses. Pyrite {FeSt: iron 46-6, sulphur 534 per cent). Pyrite or iron pyrites occurs very commonly in the magnesite deposits in the form of irregular grains or cubes disseminated through the large serpentine masses and the dolomitic portions of the deposits. It is not generally present in the magnesite itself, nor in those portions of the deposits in which the proportion of dolomite is small. Sphalerite {ZnS: zinc 67, sulphur 33 per cent). Sphalerite or zinc blende was observed at a few points in the magnesite deposits associated with the disseminated pyrite in the form of irregular, brownish-black grains. It has been found in abundance at only one point, namely, along the southeastern margin of the main pit on the McPhee property (lot 15, range IX, Grenville township). There, a iens of coarse grey dolomite, 100 feet long and 20 feet wide, occurs in which sphalerite intimately intergrown with pyrite is disseminated. Magnetite {FeO: iron 72-4, oxygen 27-6 per cent). The presence of magnetite, magnetic iron oxide, was noted at a few points in the dolomitic portions of the magnesite deposits. It occurs in the form of octahedral grains up to one-half inch in diameter disseminated through the masses of coarsely crystallized dolomite. Graphite {Carbon). Graphite is not commonly present in the magne- site deposits, but was observed to be finely disseminated through a zone of serpentinous dolomiie-magnesite in the bottom of the main pit on the McPhee property. 30 ORIGIN. The deposits of magnesite found throughout the world are all regarded as having originated in one or other of three ways. The Grecian magnesite deposits, most of the magnesite of California, and many other deposits found in various parts of the world, are believed to have been formed by the decomposition of serpentine, the serpentine in its turn being a decomposition product derived from olivine-pyroxene rocks (peridotites). The transformation of the serpentine is presumed to take place according to the following formula: 3Mt!0.2SiO,.2H,0+3COi-3MgCO,+2SiO,+2H,0. Magnesite deposits occurring near Bissel in California and in the valley of Muddy river near St. Thomas in Clark county, Nevada,' on the other hand, are said to be of sedimentary origin. The Austria-Hungarian deposits were also formerly thought to be of sedimentary origin, but are now generally regarded as the product resulting from the replacement of limestone by magnesian bearing solutions. A classification of the known deposits of magnesite according to genesis would, therefore, include : (1) Deposits formed by the decomposition of serpentine. (2) Sedimentary deix)sits. (3) Deposits formed by replacement of limestone. The study of the character and relationships of the Grenville magne- site deposits seems to indicate that these deposits belong to class 3 and are thus similar in origin to the Austria-Hungarian magnesite. Decomposition of Serpentine. Since the Grenville magnesite deposits contain considerable serpentine, it might be presumed that the magnesite is an alteration product derived from the serpentine, and thus belongs genetically to the deposits of class 1. Magnesite deposits derived from serpentine, however, are generally characterized by the following featur* s: (1) The serpentine is itself an alteration product derived from roc'.s of the peridotite family, (2) the magnesite occurs as veins or veinlets or irregular masses in the serpentine, and (3) the magnesite is usually traversed by veins of chalcedony and quartz. In the case of the Gren- ville magnesite deposits, on the other hand, there is no evidence anywhere in the district that peridotite was ever present in association with magne- site deposits, while there is much positive evidence indicating that the serpentine has originated by replacement of limestone in the manner described in section 3 below; the magnesite does not occur as veins traversing the serpentine, and except for a few isolated masses a few teet in diameter, quartz is entirely absent from the deposits. It is improbable > Min. and Eng. World, vol. 44, 1916. p. 482. Min. and Sc. Prcn. vol. 114, 1917, p. 238. 31 therefore, that the magnesite masses composing the Grenvtile deposits are directly related genetically to the serpentine with which they are associated. Sedimentary Deposition, The rocks adjoining the magnesite deposits, in so far as they are exposed, consist in the main of quartzite, garnet gneiss, and crystalline limestone belonging to the Grenville series. The association of the magnesite with these metamorphosed sediments might, therefore, indicate that the deposits were of sedimentary origin; but the Grenville series originally consisted of interstratified beds of shale, sandstone, and limestone, sediments differing in no respect from well sorted marine deposits laid down during more recent geological periods; and, it is generally assumed on the basis of both geological and chemical evidence that magnesium carbonate would not be deposited in large masses under such onditions.' However it has been suggested by Daly' that in Pre-Cambrian time conditions of marine deposition were strikingly different from those prevailing at a later stage in geological history, the ocean I "^ing nearly limeless. But the very existence of the Grenville series, which includes a large proportion of limestone, seems to disprove this hypothesis. The Grenville series had originally a minimum areal extent of at least 150,000 square miles and whether the thickness of nearly 18 miles assigned to the series in eastern Ontario by Adams and Barlow* be an excessive estimate or not, the wide extent of the series and the fact that the floor upon which the series was laid down has nowhere been observed seem to indicate that the thickness is at least many thousand feet. Furthermore, the Grenville series throughout the greater part of its extent has been intimately intruded by pyroxene gabbro, pyroxene diorite, anorthcsite, and related rocks, by which the limestone member has beon pirtly or completely metamorphosed to diopside, serpentine, phlogopite, and many other magnesian silicates; and the larger part of the analyses of Grenville limestone, contained in geological publications, has been made from specimens collected without regard to these geological relationships or the possibility that the m znesian content of the rock had been increased by contact metamorphism. Yet despite this random selection of material many of the analyses of Grenville limestone show the magnesia content to be less than 2 or 3 per cent.* It must be concluded, therefore, ' Van Hue, C. R.. U.S.G.S. Mon. 47, 1904. pp. 802, 808. Clarke, F. W., "DaU of Geochemistry." U.S.G.S., Bull. 491, 1911, pp. 534-545. Johnatoj, J., "The lolubiUty product conttanta of caldum and magnesium carbonate," Jour. Am. Chem.Soc, yol. 37, 1915, p. 2001. Redlich, Karl A., Die BUduns des Magnesits und sein naturliches. Vorkommen, Fortadiritte der Min., Krist. und Petr. vol. 4, 1914, pp. 9-42. • BuU. Geo). Soc. Am., vol. 20. 1909, pp. 153-170, Am. Jour. Sc., vol. 23, 1907. p. 93. • Gcol. Surv., Can., Mem. 6, 1910, p. 33. < Miller, W. G. and Knight. C. W., "The Pre-Cambrlan geology of •outbeaatem Ontario," Bur. o Mine*. Ont.. 1914., pp. 21, 77, 86. Fnchrtte, H., Mines Branch, Dept. of Mine*, Can., Sum. Rept., 1914, pp. 36-37. 32 that in so far as the deposition of magnesium carbonate is concerned, conditions of deposition in early Pre-Cambrian time in the Grenville district were probably not essentially different from those in more recent geological epochs, and. if this were the case, it is very improbable that the magnesite deposits are of sedimentary origin. Replacement of LimeUone. Among the more important data that might be cited in fawur of the hypothesis that the magnesite contained in the Grenville magnesite deposits has been deposited by replacement of limestone are the following: (1) In the section of the memoir in which the structure of the magnesite deposits was descriljed. pages 26 and 27. it was pointed out that the magnesite was banded in places, the difference in the bands bcmg partly due to difference in colour and partly to variations in the pro- portion of disseminated serpentine in different bands; but. the Grenville limestone commonly exhibits a banding strikingly similar to this, the only difference being that in the case of the limestone the disseminated grains in many places consist of diopside or partly serpentinized diopside as well as serpentine (Plate IX.') The similarity of this phenomena in both the limestone and magnesite seems to indicate that there is. in some way. a close genetic connexion between the magnesite and the Grenville limestone. . (2) In numerous localities not only in the Grenville district but throughout a considerable part of the region in which the Grenville series is found, the . stalline limestone member of the series contains nodular masses .f cii intine. or diopside partly altered to serpentine, which in some cases, are several hundred feet in diameter. The presence of such masses in the limestone can scarcely be explained by any other hypothesis than that they have been formed from the limestone by silication. . . . . . . r- •« (3) In many localities throughout the region in which the Grenville series is found, there are also extensive masses of rock generally known as "pyroxenite" with which the mica and apatite deposits of eastern Ontario and Quebec are associated. These masses are composed of diopside, scapolite. phlogopite. apatite, feldspar, quartz, calcite, tremolite, actino- lite serpentine, tourmaline, chaba-'.ite, stilbite, zircon, vesuvianite, and other minerals of similar character. It is believed from the association of these masses -vith limestone, from the abundance of lime silicate and pegmatitic minerals which they contain, and. from the high lime content of the deposits as a whole, that they have been formed from the limestone through the agency of pegmatitic magnesia-rich solutions.* Tnt ohoto«T.ph reproduod u PUtt IX wM Uken »t the town of Bucklnthmm. rttiutrf JO mUci to ^IJ^^^Gr^^i^^. but «hlbiU . f«tu« -hich «n b. ob«r«d .l»o« .v«y,h«. to tbe Grenville Uouetone. tTnuu. Can. Min. In*., vol. 19. 1916. pp. 349-370. Gcol. Sunr., Cm., Sum. Kept., 1915, pp. ISC-lWt. S3 (4) In places massefl of dolomite occur associated wit' serpentine contained in the limestone, and in a few localities the dolomite can be seen to be distributed irregularly along fractures traversing the lime< stone. (5) The rocks of the Grenville series have been intruded almost everywhere by bosses and thin lit par lit injections consisting of pyroxene gabbro, pyroxene diorite, pyroxene syenite, diorite pegmatite, and syenite-pegmatite, and it would, therefore, seem probable that the solutions by which the limestone was transformed into diopsidc and other minerals emanated from these intrusives. (6) The association of diopside and phlogopitc with the Grenville magnesite deposits indicates that there is a genetic relationship lx;twecn the magnesite deposits, the masses of diopside and serpentine found in the limestone of the Grenville series, and the metamorphic "pyroxenite," and that they have all been formed in some way by the transformation or replacement of limestone. On the whole, therefore, there is considerable positive evidence in support of the hypothesis that the magnesite deposits have been formed by the silication and replacement of Grenville crystalline limestone; and, on this assumption it is possible, from the character and relationships of the deposits, to outline approximately the manner in which this trans- formation took place. The probable order of events by which the magnesite deposits of the Grenville district were formed was as follows: (1) silication of lime- stone to diopside and the formation of phlogopite in places, (2) for- mation of serpentine in places, (3) replacement of limestone by dolomite, (4) replacement of dolomite by magnesite. and (5) the alteration of diop- side to serpentine. As regards the origin of the serpentine associated with the magnesite deposits, it is difficult to determine whether this mineral replaced the limei. directly or indirectly through the alteration of diopside, and both >,. ..lese possibilities have, therefore, been included as stages 2 and 5 in the formation of the magnesite deposits. In the case of the inclus- ions of serpentine, which occur associated with the Grenville limestone, there is direct evidence to indicate that the serpentine has been derived from diopside, but this transformation presumably takes place according to the following equation: 3CaMg (SiO,), -t- 3C0, + 2H,0-3MgO. 2SiO,, 2H,0 + 4SiO, -|- 3CaC0i and should, therefore, be accompanied by the setting free of considerable quantities of quartz, whereas as far as was observed quartz is not present in association with the serpentine of the magnesite deposits. From the occurrence of the dolomite as scattered inclusions in the magnesite, it would appear that the replacement of the limestone by magnetite wm effected in a manner •omewhat simiUr to that originally •uggetted by Redlich for the magnetite depoHit. of Au.tna-Hungary. namely, by two chemical reaction*, dolomite being formed m the first reaction and the magnetite in the lecond.' The lecond reaction wa. not carried to completion, however, throughout the Grenville magnetite depositt and in consequence included remnanU of dolomite remain disseminated through the magnesite. The reactiont according to Redlich were at followt: (1) (aCO, + MgCO, - MgCaCO, + CaTO,. (2) MgCaCO, + MgCO. - 2MgCO, + CaCO... DETERMINATION OF LIME CONTENT OF MAONESITE AND M AGN ESITE- D JLOMITE. Physical Characters. In mining the magnesite from the GrenviUe deposits it is customary to remove the dolomitic material as far as possible from the ore by cobbing: and. since in this operation the pre>*encc of the dolomite is determined only by such differences in appearance as distinguish magnesite from dolomite, the relationship of the l.me content of the magnesite-dolomite to its physical character is of practical importance. From the determinations of the percentage ol lime con- tained in the samples described in Tables I to VIII. the following general conclusions are inferred. Cream-white, medium to fine-grained, glistenmg magnesite usually contains less than 7 per cent CaO. Snc.w-white, medium or fine grained glistening magnesite usually contains less than 11 per cent CaO. Milk-white, medium or fine-grained glistenmg magnesite usually contains less than 12 per cent CaO. Grey magnesite is generally more highlv dolom.tic than either cream-white, snow-white, or milk-white maten. but there are a few striking exceptions to this rule. • » i in Dull white material is dolomite and contains approximately JO per cent CaO. . , ..... , .. „ Coarsely crystalline material (that is, material exhibiting cleavage faces generally greater than one-fourth inch in diameter) is usually dolomite and contains approximately 30 per cent TaO. Action ofConcentratedHydrochloricAcid. Since dolomite is much more soluble in hydrochloric acid than magnesite. the percentage of dolomite contained in the Grenville magnesite can also be approximately deter- mined from the behaviour of the material when treated with cold concen- Hun««!an tr^t. «.d now reg«d. th. «pl«em«.t of Un«toa. by m.^»lte .. 0.e fir« op«.Uon. and the (ormation of dolomite u llM iccoBd. a .*, trated hydrochloric acid. In practice it was found that th).> acid had usu- ally no apparent effect un fine to motiium-grainrd maKnt'sitc-dniomite in which less than 7 per cent of lime was present, that a feeble cfl rvescencc in widely separated spots occurred on nuiKnesite-dolomite containing less than 12 per cent CaU, and that more than a feeble ctTerveticence in widely &eparated spots indicated that the percentage of lime present was greater than 12 per cent. It was also found, however, that coarsely crystalline material did not etTervcsce as readily as fine-grained magnesite dolomite. Calcination. The percentage of CaO contained in the magncsite- dolomite can also be approximately determined by means of the difleronce in colour of the magnesite and dolomite after the material has been calcininl. Thus in the case of the cut face of the specimen of magncsitc- dolomite shown in Plate VII B, the total area of the inclusions of dolomite amounts to approximately 8 per cent of the area of the whole face, and since dolomite contains approximately 30 per cent of I aO, thi- specimen contains approximately 2i per cent CaO. This determination is probably within one-half per cent of the CaO content actually prestiit, for the specimen shown in Plate VII B was selected as the best grade of material represented in area No. 117 on the McPhee property (lot 15, range IX, Grenville township), the lime content of which was determined by chemical analysis to be 3-93 per cent (Table VII, p. 55). EXPLANATION OF TABLES AND OUTCROP MAPS. For the purpose of determining the variation in quality, the extent, and the relationships of the magnesite and maRnesitc-dolomite contained in the Grenville deposits, the outcrop maps shown in Map 1679 were prepared by means of the plane-table, alidade, and chain. In preparing these maps, those parts of the out(roi)s underlain by magnesite and magnesite-dolomite were subdivided into numbered areas, material of the same physical character and quality being included as far as possible in the same area. From each of these areas average samples were procured by collecting chips from each square f(X)t of surface. Since in practice, however, it is customary to remove serpentine and dolomitic material from the ore as far as possible by cofjbing, cobbable material of this Class was not included in the samples. The physical character and the lime content, etc., of the samples collected from the various areas are indicated in Tables I to IV, VI, and VII, accompanying the descrip- tions of the various properties. In these tables, colour, lustre, grain, percentage of material cobbed, and composition of material cobbed are indicated. Under the heading grain, the magnesite is classified as fine, medium, or coarse, according 36 as its grains are less than J of an inch, | to i of an inch, or greater than } of an inch in diameter, respectively. In Tables V and VIII a summarized statement of the number of feet of magnesite, magnesite-dolomite, and serpentine contained in diamond drill cores obtained in lot 15, range XI, and lot 15, range IX, Grenville township, is included. 37 ^ '1 CHAPTER IV. DESCRIPTIONS OF PROPERTIES. GENERAL STATEMENT. In the following chapter the deposits of magnesite and magnesite- dolomite so far discovered in the Grenville district are described and the tonnage of magnesite and magnesite-dolomite known to be present in each deposit estimated. A list of the lots on which the various deposits occur and of the owners of these lots is included in the following table: Lisl of Properties. Lot Range Township Owner 13 1 Harrington. Grenville. International Magnesite Co., Ltd. 18 11 North American Maghesite Co., Ltd. 15 11 u Scottish Canadian Magnesite Co., Ltd. 15 10 u M M M U 15 9 u North American Magnesite Co., Ltd. 13 9 u 16 9 a Fitzsimmons and Boshart. 11 8, N u Campbell. 12 8. N M Fitzsimmons and Boshart. 11 8.S « u 12 8, S « « 9 11 Augmentation o( Grenville. 21 1 Harrington. Grenville. 77 10 LOT 13, RANGE I, HARRINGTON TOWNSHIP, DOBBIE MINE. The Dobbie magnesite mine, the property of the International Magnesite Company, lies near the north end of lot 13, range I, Harrington township, and near the eastern margin of the broad flat which adjoins Rouge river in the southwestern part of Harrington township. The outcrop in which the magnesite is found has an areal extent of approximately 300 by 200 feet, but at the time the deposit was visited by the writer in January 1917, only an area 25 by 50 feet, where mining operations had been commenced, was visible through the heavy cover of snow. The part of the deposit being mined averaged 7 • 5 per cent CaO.' It consisted in part of glistening white magnesite and, in part, of medium to coarse-grained, grey material containing disseminated grains of dark green serpentine. ■ According to uuUytn by J. T. Donald and Co. of Montreal. 38 A series of samples from an area about 100 feet square on the surface of the outcrop was collected and analysed by J. T. Donald am? Company of Montreal and was found to carry the following lime content: Sample No. (1) (2) (3) (4) (5) W (7) (8) W, "O) ("I Per cent CaO 6 58 7-72 10-45 7-26 7-72 1119 10-68 7-94 4-77 10-68 15-77 Average omitting No. 11 8-50 An average sample from a shipment of mc^nesite from the property was also found to have the following composition:' Silica }-60 Iron oxide and alumina I'Ji Lime .If. Magnesia. 39-25 Loss on Ignition tvii The quality and extent of the magnesite already known to be present on this property seem to indicate that the quantity of ore actually present may be extensive, but much development work is required before this can be positively determined. All that can be stated at present with regard to the deposits is that, on the basis of certain assumptions inferred from the study of the magnesite deposits as a whole, it is calculated that at least 25,000 tons of magnesite ore is present. The data on which this estimate is based are as follows: Known horizontal extent of deposit, 10,000 square feet. Assumed depth, 50 feet. . , ■ j:n Assumed proportions of magnesite present in deposit, oO per cent. Number of cubic feet of magnesite in one ton, 12. Accompanying the magnesite there is also probably present at least 8,000 tons of magnesite-dolomite. A number of camp buildings have been erected on the property. LOT 18, RANGE XI, GRENVILLE TOWNSHIP, SHAW MINE. This property is situated at a distance of approximately 15 miles from the Canadian Pacific railway, and, on this account, is operated only in the winter, when the cost of transportation to the railway by sleigh is $2.50 per ton as compared with a cost of $4.5C in the summer. At the time the outcrop was examined by the writer in July 1916, the sur- face of the magnesite was so covered by broken rock, left at the close of the previous winter's operation, that maenesite in place could not be seen except along the southern face of the pit and in a low ledge projecting through the rock debris near the north end of the deposit. The rock outcrop in which the magnesite is found originally formed a low northeasteriy trending ridge, but it has been excavated down to the same elevation as the surrounding flat except at its south end where a face from 10 to 20 feet high remains, out of which an extension of the > AccoidiiK to laalysM by J. T. Donald tad Co.. of Montnal. 1 1 39 main pit from 15 to 20 feet wide has been excavated southward for a distance of 50 feet. A diagrammatic section across the face of this extension is shown in Figure 2. It is stated by Mr. Broadbent, who examined the depoait in 1900, that the magnesite is intersected by a small dyke of porphjrrite.* This dyke was not observed in place by the writer, but a number of fragments of black aphanitic diabase porphyry were observed on the dumps which were probably derived from the intrus- ion referred to by Mr. Broadbent. OcfotietJ Survty, C*rmd*. Figure 2. Diagrammatic section across south face of pit in magnesite deposit, lot 18, range XI, Grenville township. Descriptions of the physical characters and the chemical analyses of samples from the magnesite deposit on the Shaw property are included in Table I. Samples Nos. 1 to 17 were collected from areas on the south face of the southern extension of the main pit as shown in Figure 2. Sample 18 was taken from a mass of magnesite exposed near the north end of the eastern face of the southern extension of the main pit, and samples 19 to 22 were taken from the projecting ledge of magnesite exposed near the north end of the deposit. Sample 23 represents the average of a small pile of ore remaining in the middle of the pit. The remaining samples (Nos. 24-35) were collected from the surface of the outcrop by Mr. Broadbent in 1900 and were described by him in the report of the section of chemistry of the Geological Survey for that year. ■ Geol. Sunr., Can., Ann. Rept. vol. XIII, 1900. pt. R, p. IS. 40 Since the Shaw property was examined by the writer a single dia- mond drill hole has been drilled on the property to a depth of 64 feet with the following result: Number of feet Number of feet Number of feet containing less than containing more of serpentme. 13 per cent CaO than 13 per cent CaO 23J 23 17J At a depth of 35 feet a marked increase in the per cent of lime occurred in this core, but this may possibly be due to the fact that a lens of dolomitic material was encountered at this point. Owing to the poorly exposed condition of the magnesite deposits at the time it was examined, and the absence, except for the single drilling record, of information with regard to the depth to which the deposit extends, the data necessary for even an approximate estimate of the total tonnage of magnesite present on the Shaw property are not available; but, on the basis of certain minimum assumptions, an estimate of the approximate number of tons of magnesite in sight can be obtained. The data on which such an estimate can be based are the following: Approximate superficial extent of deposit, 15,000 square feet. Assumed average depth to which deposit extends, 25 feet. ftoportion of magnesite averaging 10 per cent CaO in deposit, 50 per cent. Proportion of magnesite averaging 16 per cent CaO in deposit, 20 per cent. Proportion of serpentine in deposit, 30 per cent. From the preceding information it can be calculated that there is present in the deposit approximately 15,000 tons of magnesite averaging 10 per cent lime and 6,000 tons of material averaging 16 per cent lime. It is, of course, possible that the deposit extends to a greater depth than 25 feet; but, in view of the results obtained from the single hole drilled, a greater depth could not be safely assumed in making a definite estimate of the tonnage. Similariy, it is possible that the superficial extent of the deposit may eventually prove to be greater than 15,000 square feet, but further development work is required before this can be determined. The percentages of serpentine and magnesite present in the deposit were determined partly from the information contained in Table I and partly from the known general character of the magnesite deposits of the district as a whole. A two-story camp building having accommodation for about twenty men has been erected on the property. 41 dia- feet TaNi I. Physical CharacUr and Chemical Composilion of Samples of Uainesilt from Outcrop on North Half of Lot II. Ranf XI. Grnuilli Tomnship. lime % lens i (osits 1 ingle s the 1 ite of 'I i not 1 mate | ined. I ;re is aging lime, iepth hole finite rficial 5,000 s can ;nt in ed in nesite about No. Colour Lunre •now-white, •now-white, •now-white. white white blue-grey . , . •now-white, •now-white. white white. white, white. white grey white white snow-white. . cream-white, pinic gliitening . glistening, glistening. dull glistening. dull glistening, glistening. duU cream-white, snow-white... glistening. glistening. . . glistening to dull glistening. . . dull dull dull glisteniiig. . . dull dull to gliit- ening dull to glist- ening dull snow-white -listening.. Average sample fr.on ore pile, blue-white blue-white milk-white milk-white blue-white grey to reddish . . . white ireyish-white. ... greyish-white and reddish-white grey-white blue-white translucent snow-white subtrmnslucent Average sample fr ora surface of Grain CaO MgO fine fine line line fine fine medium. . . . medium .... fine to medium medium to | coarse *ine medium granulated medium. . . . fine granulated . fine compact medium .... fine compact fine fine. 8.77 6'M 7-96 14-90 11-87 11-96 11-25 12 18 8 33 40-28 40-48 40 M 34-38 31-82 38-02 37-78 35-70 39-40 14-31 i 35-74 fine to medium fine coarsely cryitalline fine fine fine fine fine fine fine to coair' coarse... medium medium . . outcrop. 087 1117 9. 80 15-86 9 95 10. 48 10-44 8-58 1176 17. 50 6-45 10. 16 900 10. 58 8. 75 604 8-96 7 36 '88 mall p^.-j centage 9-12 37. 02 37-36 35 -OX 33-08 37-94 36-46 37-60 .19.56 M'lO 3212 40 '.S4 38 02 37-35 33 45 38-17 .16. 73 36 22 36. 61 23-66 oJ-93 39-36 40-46 45-36 36 68 Equivalent to i Silica and . . insoluble CaCOi 1 ;.li._ ,/i matttt. 15. 60 12-20 1421 26-60 21-20 21-35 20-40 21-78 14 87 25 - 55 1 55 19-94 17-50 28-32 17-77 1871 18. 64 15 32 21-00 31-25 11-52 1814 16 07 18- 89 15-57 10-78 1600 13 14 .10-14 19-71 12-36 10 80 84 18 1 84 60 1 84-9S 1 71 86 66 50 79 26 78 96 74 61 82 34 74 70 77 .8 78 08 73 32 69 14 n in 76 ?i) 78 58 82 64 75 44 67 12 62 20 84 72 79 46 77 62 74 68 78 08 77 16 76 09 76 97 49 71 75 69 82 72 85 00 95 SO " 07 050 2-90 0-88 216 22-UO 0-10 1-50 610 2-32 0-30 26-40 2-20 2H 04 2-00 238 3-30 0-90 0-80 2 24 0-64 11 40 2. 36 1. 84 Analyse* 1-23 by Mr. H. A. Leverln of the Mines Branch. Department of Mines, Ottawa. Analyse* 24-34 by Mr. F. G. Walt. Gcol. Surv.. Can.. Ann. Rep., 1900. pt. R, pp. 14-17. LOT 15, RANGE XI, GREKVILLE TOWNSHIP. On this lot a series of three exposures of magnesite, magnesite- dolomite, and serpentine, occur along the eastern margin of the flat which extends southward from Grenville lake at the south end of the lot. These outcrops numbered from south to north are known as Nos. 1,11, and III respectively. The descriptions of the physical character and lime content of samples from the surface of these outcrops have been tabulated in Tables II to IV, while the proportions of magnesite, magnesite-dolo- mite, and serpentine contained in diamond drill cores obtained in drilling operations on the property by the Harbison -Walker Refractories Company of Pittsburg are summarized in Table V. 42 Outcrop No. I. Magnesite of No. 1 quality is known to occur along the southern and southwestern margin of this outcrop, and in the vicinity of diamond drill hole No. 15. A summation of the proportions of magnesite, magne- site-dolomite, and serpentine exposed in the southwestern portion of the deposit (outcrop No. I, and table II) is as follows: Per cent. Magnesite *J Magneaite-dolomite » Serpentine 3" A similar summation for the diamond drill cores obtained in this area and from hole No. IS (see table V) is as follows: Per cent. Magnetite ^ Magnesite-dolomite »» Serpentine *' It can be safely assumed, therefore, that in these portions of the outcrop the proportion of magnesite containing less than 12 per cent lime is at least 60 per cent. From the examination of the various deposits in the district it is inferred that, as a rule, the quality of the material obtained from a drill hole will be maintained horizontally for a distance of at least one-fourth the depth of the hole in either direction along the strike of the deposit and one-eighth the depth of the hole in either direction at right angles to the strike. On the basis of these assumptions the following data are available from which the number of tons of magnesite in sight in No. I outcrop can be estimated: Superficial area of deposits adjacent to diamond drill holes Nos. 11, 8, and 10, *'*°Prov^^dl^th to which deposit descends in area adjacent to drill holes Nos. 11, 8. '"'^ Total h^zontal extent of deposits adjacent to diamond drill holes Nos. 12, 13, 20, ""* ProvKerTge"' dipth to which deposit descends in the vicinity of diamond drill '"'^o^rtionofmagnesitlVn^^^^ Proportion of magnesite-dolomite in deposit, 10 per cent. Number of cubic feet of magnesite in 1 ton, 12. The tonnage of material present in the deposit is, therefore, as follows: ... Magnesite. Magnesite- dolomite Adjacent to drill holes Nos. 11, 8. and 10. .. 12,000 tons 2,000 tons. '^'^'20;"and'r5''"''.''°'.'°'".^'°''. '^' .".' 180,000 tons 30,000 ton. Total 192,000 tons 32,000 tons. 4S In thoM parts of No. I outcrop not included in the above estimate there is exposed iipproximately 7.000 square feet of rock surface composed as follows: Magncdtc, S per cent. MagnMitCKloioniite, •vcraging le per i Serpratiae, diopside. ud quarts, 3D per cent. MapiettteKlaloniite. •veraging 16 per cent CaO, 62 per cent. Most of these areas are scattered over the surface of thf outcrop, and it is only in the vicinity of diamond drill hole No. 18 that a mass of magnesite-dolomite of workable dimensions is known to occur. At this point approximately 5,000 tons of magnesite-dolomite are present. I r«N> tl. Pkytifl Chmttm tat Limt Caalml ffSamtht of Uttmaiu fnm Owlirof So. I. Lot IS. Rtnf Xt, Na 9 I 9-21 24 Colour niNy-whiM. whlte-trcy.. whit* inow-whit* Olid cnam- wUte white w-whitc •aow-whitc to trey. white. . . craam white. . . white to grey.. cream white to white white irty to white.. •hinlB(-4ull. iUetcnliif . . gUeteninf. . . gUftenlng. glleteniiig and white to grey. irey-whiM •hlnlng dull to gUetenlng. gllwenlng. grey-white grey-white mow-wblte grey grey grey white to grey mlllt-wbtw to grey. white to grey. grey-white -hlte. snow-white, white milk-white to enow- hite grey •now-white to milk- white grey-white snow-white •now-white white •now-white od milk- white •Deckled grey now and milk-white. •now-white •now-white Liutrt •hlalag gllnenlng duUtogUatciilat gliatenlng gliatenlng gliatenlng gliatenlng to dull, gliatenlng to dull., dull to glmenlng. . gliatenlng to dull gliatenlng to dull. gliatenlng and dull glleteniag dulltogUatenlng. gliatenlng. shining. . . gliatenlng to •hlnlng shining gliatenlng to dull. duU glletening gliatenlng dull to ehinlng. . gliatenlng. Crala fine. covae. fine.... fine fine. . . fine... fine fine fine to medium fine and coarse.. fine to fine, fine. fine fine fine fine fine fine medium . . fine to medium medium . . . fine medium to coarae fine medium to coaree medium to coarse coarse fine fine fine fine medium to coarse fine •hlnlng to dull... [coarse. glistening fine. glistening fine. glistening ifioe. Percent ofcob. nU 2$ aU nil dU oil 40 nU nU 25 nil nU nil nil nU nil nil nil 20 nil 20 nil 10 nil nil 20 nil to nil 50 nil nil nil nil nil 25 nil nil Material cobbed grey magaetlti lomlte dolomli coarse white dolo- mite grey magnesite- dolomite white dolo- mite coarse white dolo- mite dull white dolomite. serpentine. serpentine. yellow serpentine . serpentine. dull white and grey dolomite serpentine. Per cent of CaO 22'00> 9'66> 22'00> 9001 l« 00> 9'a0> I0'00> 7 00> 6'96> 13 00> I3'00> 20 001 I4'26> I9'90i 13 J5> UOQi 13'00> 15'00> tili' IS'00> ll'66> I3'00> I2'00< lt'0O> 1800 I3'00< Ig'OO' 22'00> ll'00> I5.00> 000' 12'00> 20'00< 9-74« 21 -SO" ll'Oa< g'OOi 4'«4> Per cent o( CaO in ma- terial cobbed* 1500 1400 18 00 26-00 28 00 2900 44 TM* n.—CoiUiiuu4. No. 4S M 47 48 49 SO SI S2 ss S4 SS S6 S7 S8 S« «0 61 62 63 64 6S 67 68 Colour Liutra Gimin grey to tnow-whltc — •pcckird grey •now-whiw grey ., •now-white to blue grey grey to snow-white . . . •now-white to grey... •now-white gray to mow-whlte. . . mow-white w-white tny.--- •now-white — .• grey to (now-white. . . glistening to dull.. glietening gllatening gUetening gllatening gliatening gUeteoing gllatening glUuning gllMenlng glistening gliatening gliatening gliatening Percent . . ^^ . o( cob. MnterkI cobbed Sne medium fine medium. Ane fine Am Aae jw-white to milk-white •now-white •peckledgrey. •pcckled grey, irey gliatening. gllauning. 69-71 72 7J 74 7S 76 77 78 79 80 81 82 «rey white apeckled grey. grey and mow-whlu. . fine fine medium . Ane medium. Ane. Ane. grey, grey. grey to white white and •peckled grey gray rhitetogrey •now-white., •now-white, anow-white. white. ahlning toduU... gllatening to dull, glistening dull to gliatening ahlning dull to ahlning. . . gliatening and shining glistening glistening to shining dull to glistening. medium . . . Ane ■nediumto white, r-white. glistening dull to gllatening gliatening to f^iwtng gllatening gliatening gliatening gliatening gllatening. gliatening. medium to coarae medium . . Ane to coarae Ane and coarae medium . . ■ medium to coarae medium to coarae medium . . An* Average aample from pile tone) excavated from Average aample from pile tona) excavated from of ore (containin aample areaa 7S- ofora (containing aample area 82 Aac. Ane. Aot. Ane. Ane. g approxim 81 approxima 25 50 S 25 nil nil nil nil nil 25 nil S nil SO 10 s nil nil nU nU nil nil nil nil 25 nil 25 nil nil nil 25 30 5 20 10 aerpentine. aerpentine. aerpentine. aerpentine.. Percent ofCaO Per cent of CaO in ma- terial cobbril' serpentine. . aerpentine. . coarsely crystalline white dolomite green serpentine. . . coarsely ciystalUn: white doMmite aerpentine. coarse dolomite . ately900 serpentine serpentine serpentlnouadolo- mlte-magneaiu green serpentine... green serpentinous material 12 oa> 19'00> 7-00> i4.ao> 8 00> 9.00> 9.00> 7.00> 8 14> 10'00> 5 00> U00> 8'86> lOOO- 9.00> 7.00> UOIX 16 00> WOO" 14.00> 16.00> 1S'00> 15 C" 14 00< 13 00> 16'aO> 11 oa> 14'00> tsooi 10-76» ii'ao> llOOi 716« 10'00> lOOOi 28-00 27. 00 lely 1,000 8.74> 9-92' 2S 00 1600 IS 00 1 oSS^toid by Miss D. U. Stewart. Mine. Branch. Department of Minee. Outcrop No. II. Magnesite and magnesite-dolomite are known to occur in this outcrop at four points. (See map 1679 and Tables III and V). On the basis of assumptions similar to those made in the case of No. 1 outcrop, the number of tons of magnesite and magnesite-dolomite in sight in each of these localities is estimat«i^as follows: ^ ^^ _^^^^^.^^ Locality magnesite. dolomite. Adjacent to diamond drill hole No. 23 . . _ . . . . 9 , 000 1 . 500 Adjacent to diamond drill holes, Nos. 22, 24, ^^ ^^ 17,000 Adjacent to diamond drill holes js'os. 27 anil 28 2.500 ^°" Total ^'^'^ '^''^ 45 'n cent nf ftO In ma- rial cobl»"l> TMt lit. Pky$ial Cktndm and Um§ Conttnl af StrnfUi cf MofiMiiU from OnUrop Na. II, La IS, it««|< XI, CrmiUt Temntkip. 27 '00 4 •1 i 29 00 1600 15 00 I this . On No. I lite in esite- — > No. 2 i 4 5 6 7 n 10 II u IJ 15 16 17 18 19 20 21 22 23 24 2S 26 27 29 30 31 32 33 34 3S 36 37 38 39 40 41 42 43 44 45 grey •now-whlu to mUk-whlte while to irey mow-whlte •now-white to frey. •now-whiw to mr. w-white mow-white tveraie Mtmple from pile ■now-white snow-white «rey ■now-white Riow-whiu. mow-white. , ■now-white. mow-white, •now-white, ■now-white. Colour dull fliatening ■liMenini and dull gliatenlni. ■U^tenlnf. flletenlnf. gli^teninf. glistening of ore excavated (r gliatenlng S listening ull gliatenlng gUitening. grey grey and pink, ■now-white. . . . mow-whlte. ■now- white. glistening, gliatenlng. glistening... . gliatenlng gliatenlng to ahining gliatenlng. . . grey and snow-white. grey ■now-white to milk-white white. mow-white . ■now-white . ■now-white snow-white ■now-white mow-white ■now-white •now-white snow-white ■now-white cream-wliite cream-white and grey. white and grey cream-white and grey . . crecm-white and grey . . mow-white grey to cream-white . . . Luatre line, flnc. Rne. flne Roe Ane Kne rnuiu- lated fine om pit at 9 fine fine fine fine fine. glistening to dull and ahining glistening gliatenlng. gliitening. gliatenlng ahining and gliat' ening shining and gliat' ening shining glistening, gliatenlng. gliatenlng . glistening. . gllttening.. gliatenlng.. gliatenlng.. gliatenlng. . gliatenlng. . gliatenlng. . glistening. . glistening. , glistening. glistening. glistening. glistening. glistening. Grain fine fine to medium fine fine medium. . fine to medium fine to medium fine fine, fine. fine. medium to fine medium . . . medium to coane fine fine fine, fine, fine. fine, fine. fine granu- lated fine granulated fine fine fine, fine, fine, fine, fine, fine. Per rant cob. nil 20 nil 50 nil 20 2 nil nil nil nil SO to 20 S nil nil nil 25 25 nil 75 SO 25 40 nil nil 2 nil nil S nil 10 nil nil 30 40 SO 2S SO s 5 30 serpentine dull white serpentln- ous material serpentine grey magnealte dol- omite serpentine. grey magneaite-dol. omite grey magnealte-do|. omite magnesite-dolomlte dull grey magnesite- dolomite dull grey dolomite . . coarse grey magnes- Ite-dolomite grey magneaite-dol- omite Per cent Per aent o( Material cobbed L'aO CaO In ma- Itrrial cobbed coarae grey magnea- ite-dolomlte grey magneftite* dolomite grey magnesite- doioniite grey magneaite- dolomite coaraely crystalline magneaite-dolo- mite grey magneaite- dolomlte grey ma^eslte- dolomite dull white dolomite grey magneaite- doiomite grey magnesite- dolomite grey magnealte- dolomite grey magnesite- dolomite gray magnesite- dolomite grey magneaite- dolomite aerpentine 20 00" 10 ao< I3'00> l|.00< to 00 12 00 U'70i 11 001 <»-3.?> 4 00 10 37« I6.00> II'OOI I3'49> 9'00> 12 00> MOO' I2.00> l|.42< 12'00< lO'OOi 918« 10'00> 900' 1000' 13'00> 9 00> UOOi 10 00' 9-78" 7 00' 8001 1300' 900' 1000' 700' 9'00> 7 00' 900' 900' 1300' 8-68 900' 1000' nooi 12 00 IS 00 14 00 1400 13. 00 IS'OO 2000 15 00 14 00 is 00 IS'OO 1600 14 00 IS'OO 14 00 24 00 IS'OO 15 00 14 00 1300 13 00 14 00 ' Estimated. ■ Determined by Miaa D. M. Stewart, Mines Branch, Department of Mines. The data from which the p'}ove ettimatet were made follow: DtfotU a4joetnt lo drill M* 1$. Horitonul extent, 2,100 KiiMre feet. Proved depth, 90 (eet, CompMition: magnetite, 60 per cent; magnecite-doiomitc, 10 per ceM; eerpcn- tine, 30 per cent. Dipotil adjactnt lo diamond drill hoUt, Not. it, Z4, omd IS. Horisontal extent, 6,500 iqiuire feet. Proved average depth, 135 (eet, Compoution : magneMte, 40 per cent; magneeite-dolomite, 25 per cent; Mrpentinc, is ptt cent. Diporitt adjactnt lo diamond drill koUs i'.ut. 27 and U. Horixontal extent hole 27, 600 square feet, and hole 28, 600 square feet. Proved depth, 50 feet. Composition : magnesite, 50 per cent ; magnesite-dolomite, 5 per cent ; aeri^^entinc, 45 per cent. Number of cubic feet of magnesite and magnesite-dolomite in 1 ton, 12. Unexposed Area Between Outcrops II and III. In the unexposed area between outcrops II and III there are three diamond drill holes (see table v) which ha^'e disclosed the presence of approximately 90,000 tons of magnesite-dolomite. The data on which this estimate is based follow: Horiiontal extent, 20,000 square feet. Proved depth, 80 feet. Composition: magnesite-dolomite, 70 per cent; serpentine, 30 per cent; number of cubic feet of magnesite-dolomite in 1 ton, 12. OuUrop No. III. There is exposed in outcrop No. Ill (see outcrop III on Map 1679 and Table IV), approximately 25,000 square feet of rock surface composed as follows: Magnesite, 65 per cent, Magnesite-dolomite, 15 per cent, Serpentine, 30 per cent. The eight drill cores Nos. 1 to 7 and 29, obtained from di^i- jnd drill holes in the deposit and its vicinity (see Table V), are comp.. ed as follows : Magnesite, 60 per cent, Magnesite-dolomite, 13 per cent, Serpentine, 27 per cent. In calculating the number of tons of magnesite and magnesite- dolomite present in No. 3 outcrop it can be assumed, therefore, that the deposit as a whole contains at least 60 per cent magnesite, and 13 per cent magnesite-dolomite. Since diamond dri! ole No. 29 was drilled in the clay ^iat outside the outcrop the horizontal extent of the magnesite ore known to be present in outcrop No. Ill can be enlarged to include the material in the vicinity of this drill hole. 47 uw, IM, ree of On the baiii of the . jregoing deductions the following data are available from which the number of tons of magnesite and magncaite- dolonute in light in outcrop No. Ill and its vicinity can be estimated: Horitontal extent, 30,000 lauare (cct. iverage depth, 125 fe Proportion olmagnctite, 60 per cent. Proportion of magnetite-dolomite, 13 per cent. Number of rubir feet of magnesite and magneiite-dolomite in 1 ton, 12. The tonnage of magnesite and magnesite-dolomite in the deposit is therefore, us follows: Magncaite, 187,500 ton*. Magneaite-dolomite, 40,600 torn. The preceding estimates of the tonnages of magnesite and magne- site-dolomite present on lot 15, range XI, Grenville, stated in sum- marized form are as follows: Number I outer p Number II outcrop Between outcrop* II and III . Number IV outcrop Total Ugnciite tons 192,000 39,000 187i6o6 Magnetite- dolomite, tons 37,000 18,700 90,000 40,600 418,000 186,300 ibo- lap ace >nd I as ite- the per ide ent ity 4S r«M< IV. fktilttl CDrnttW tmd Lim$ < >/ at Stmflu tf Itttn-U' fnm Omifnp Wo. ///, Lai IS. *mf« XI OfwHIU Tammikit. N*. I 2 S 4 i 7 1 • 10 II U 14 IS I* IT IS 20 21 22 2J 2« 2S 26 27 28 30 31 32 J3 34 cmm-whltrinow-whllr «UMenlnf . and irey pink, cream-whllc, »>n4 ir»y crMm-whItP And snow- whttr, grey i»y Cofam Lm Gfkia n cra»n-»hite.anow-»hltr. •nd irry crekm-wliUe and •now- white pink, crnm-whitr. and irey whiM cfniB-whitt and mow- whltr cream white, pink, and •now-white rream-whlte and •now- white cream-white and anow- whlu ioow-white to craam- white ■llateninf (liwenlni iiUm n aliftri '. ■ihateri glietenl' ■hining lll^ter.Mir ■llMti glleteiun gliateninE gllatening Pet cant o I oo> 16 00> • 00 .1 9S« « ao> ti ao> • 32« 6 00> 7-00I 8 00> 7 001 3 23« «'00> 3-00> BOO* 8-57« 9-00> 1.1 00> 12 ao> 9 00" 9 mil io-ao> 14-00> 12 00' 10-88> lU ou> 15-00" 14-59" 10 00< 10 00> It-OO' Kf caul Can in BMiarial cobtwd* 49 Ttttt IV.-Cm«mm4. U 00 t.l 00 u w 1300 li 00 15'0U 1800 15 00 U'OO 14 00 18 00 2500 15-00 g S„ I « "lour (•r*ln I of cob. , MM«tlal cobbnl J* (iww-wWw to mUh-whllc KhMeiUmi |/, •no«-whU> ■tarnlna. "1 12 OU J j« 12 oil 4 )« 12 00 J 40 S ■HI ^^ 42 ■ • • ' ■ i 4.1 44 U (K 45 3 U> 12 on 4! ■ 411 1200 -1 50 ? 51 13 00 52 ' <1 14 00 54 55 16 00 ■4 5« 17 00 4 J 7 1 58 g 50 1 60 Wr 'fill Prt .-ctn ,(( I of i to Call li\ ma- J7 Aac. •iKiw-whItF nd rad. IttMnilnf . gray iliMrntniand •hlnmg ipwkled grey ' gllwrnlni . , and flhinlna cmtm-wl>l>r. nilik-whitr. g!in>Miing and and gfey Icmiin-whlir to mow- i white tnow-whilr and mllk- I white aaow-wlute and w v . . 4htnlng ^tiM«ning ig»»y. {gllnraini 'gliatrnlng dull to gUtteninf . r-«hitr ulintetilng. •now-white to grey «riow-whlte. milk-white, grey, aiHt pink inow-whitr arid milk- white iinow-white and grey. . , :Kliiitenlng gliDtening Sn« tn marm ftiie and coarH ftn* to amtm Bne flue fine lo medium ftne 6ne ftne An*. glincning glinrnlni 6ne. dm. fine. iinow-white gllnenini. . , ;inow-white, milk-white gliitening. . . I and grey i .imow-»hlte, milk-white. IgUstening ftnc. I and grey mow-white jglinening iftne linow-white. igliatening |line iinow-whlte, milk-white, gliateniog .fine. and grey milk-white and grey. . . gllMenini *ine. j milk-white and iiay glidtentng fine. snow-white glintening Anc. glittrning Iftne. gliitening Ane. [ (ij I 64 65 ! 66 67 TO ;i grey... i mow-white and milk- I white •now-white and milk- white ! tiiitk-white and grey Isnow-white milk-white gliitening fine. gliitening and dull, Ane. milk-white and grey. gliiitening. uiinening to •hining glistening . . . . 1 snow-white and milk- 'glistening I white snow-white. glistening. snow-white and milk- gluitening while snow-white and milk- glistening and white iliining milk-vthite.. snow-white. fine medli.-.'n to coarse fine to medium fine fine, fine. glistening and shining gliitening fine to medium fine to medium fine » 2S nil 5 S fiQ 25 nil nil nil nil bU 45 Itil 2« nil nil nil 25 25 nil 60 nU nil nil nil nil 5 nil nil nil 5 75 I shinliM, dull- 10 on' white, ami grey: magnesile-dolotnit,- coaree. slimmg, my\ 11 10 00* '( 00" 12 OIV 12 coarse, grey, serpen- tinoua niavneslte- dolomite aerpentine grey mMtnesits-dol- omite 10 00" « 62> »-J7> 10'00> « 0O> 10 ao> iO'ao> ij'Om 10 641 dark green serpen- tine coarse, grey, and ser- pentinous inagnes-' ite-dolomite serpentine grey, seriientinous | ; magnesite-dolomite- 11 11 u 84« 1 001 59" 13 001 7 07" 7 8 56' 9 00' lO-OO" 10 001 ' Estimated. ' Determined by Miss D. M. Stewart, Mines Branch. Department of Mines. 18 00 22 on 17 on 20 00 iii'tio 15 00 1500 Tabl* V. 50 Summary Description of Diamond Drill Cores from Uapiesite Deposits on Lot 15, Range XI, GrenviUe Toumship. No. Depth of soil Ma^nesite con- Magnesite-dolo- Serpentine Total of taining less than mite containing and depth of hole. bole 12 per cent CaO', more than 12 per diopside. cent CaO', feet feet feet feet feet Outcrop No. I. 8 nil 35 5 20 60 9 5 nil 12 33 50 10 nil 24 nil 26 50 11 nil 8 14 28 50 12 nil 104 15 36 155 13 nil 110 5 25 140 14 nil nit nil 100 100 15 10 117 16 32 175 16 nil nil 27 73 100 17 5 nil nil 75 80 18 nil nil 51 29 80 19 20 nil nil nil 20 20 20 104 36 OuUrop No. I J. 20 180 21 nil nil nil 50 50 22 nil 4 77 44 125 23 2 51 5 32 90 24 nil 102 16 22 140 25 nil 40 4 46 90 26 nil nU nil 60 60 27 nil 25 3 47 75 28 nil 26 2 47 75 Unexposed area b etuieen outcrops 11 and III. 29 5 88 31 18 142 30 11 nil 92 35 138 31 17 nil 22 17 56 32 20 nil 34 Outcrop No. III. 18 72 1 nil 67 1 52 120 2 nil 83 34 23 140 3 nil 75 30 2 107 4 nil 33 4 3 40 5 nil 66 2 30 98 6 nil 75 5 25 105 7 nil nit nil 60 60 ■Ettloated. In mining the magnesite on the property the ordinary open-cut quarrying method with boom derricks and hoists is employed (Plate XI). The large masses of serpentine and dolomitic material encountered in the pits are unloaded into cars and transferred to the dumps directly. The magnesite on the other hand, is transferred to cobbing platforms where it is broken and cobbed. The equipment on the property includes a number of boilers having a total capacity of 350 horse-power, 3 air compressors, 4 double drum hoists, 4 derriclra, numerous drills, pumps, and other necessary machinery. \ 1 51 Camp buildings for the accommodation of 200 men have been built on the property and a light railway 14 miles in length has been constructed to the deposits from a point on the Canadian Pacific railway 2 miles east of Grenville station. In laying this railway long ties were used so that in the future if necessary it could be transformed to a broad gauge track. The necessary light locomotives and cars for the operation of the railway have also been procured. LOT 15, RANGE X, GRENVILLE TOWNSHIP. Deposits of magnesite or magnesite-dolomite are known to occur in two localities on this property. One of these deposits lies at the north end of the lot and near the west side of the railway leading to the pits of the Scottish Canadian Magnesite Company on the adjoining lot in range XI. The other deposit occurs at the south end of the lot adjoining the deposits of the North American Magnesite Company on lot 15, range IX. The northern deposit occurs in association with an outcrop of diopside which extends for nearly 600 feet along the eastern edge of a ridge of garnet gneiss and quartzite. It consists largely of dolomite and, while material of better quality may possibly underlie the clay flat adjoining the deposit, in its exposed portions at least it is not sufficiently extensive to be of commercial value. The southern deposit on this property lies on the northern edge of the ridge of magnesite, magnesite-dolomite and serpentine, which out- crops at the north end of the McPhee property (lot 15, range IX, Grenville township). The extent and geological relationships of the occurrence are indicated in outcrop No. 4, on Map 1679, and the physical character and lime content of samples collected from the surface of the deposit are given in Table VI. Of the exposed portion of the outcrop, 35 per cent consists of magnesite containing less than 12 per cent CaO; 55 per cent consists of magnesite-dolomite containing more than 12 per cent CaO; and the remaining 10 per cent consists of serpentine. Since the portion of the deposit hidden by rock debris underlies the bottom of the pit where the material of best quality probably occurs, it may be assumed that the proportion of magnesite relative to magnesite-dolomite and serpentine present in the exposed portions of the deposit is at least not less than that for the whole deposit ; and from the following data the tonnage of magnesite in the deposit can be estimated. Area, 30,000 square feet. Percentage of magnesite containing less than 12 per cent CaO, 3S. Percentage of magnesite-dolomite containing more than 12 per cent CaO, 55. Assumed depth, 25 feet. Quantity of magnesite, 2,500 tons. Quantity of magneaite-dolomhe, 4,000 tons. 52 A few tons of magnesite were mined from this deposit by the Scottish Canadian Magnesite Company, owners of the property, during the winter of 1915, but since that time no work on the deposit has been attempted. Table VI. Physical Character and Lime Content ot Samples of Magnesite from Outcrop of Magnesite on Lot IS, Range X, Grenville Township. No. Colour Lustre Cirain Per cent of cob. Per cent of CaO speckled-grey dull fine nil 1800' snow-white glistening fine 75 12 00» milk-white glistening fine nil 11S6« milk-white glistening fine nil 1200' speckled-grey dull fine nil 18.00' 6 speckled-grey glistening to dull fine nil 1500 7 milk-white glistening fine nil 13 -78' 8 milk-white and grey glistening fine nil 1400 9 milk-white and glistening fine nil 1100 10 grey speckled and dull fine nil 1500 11 grey snow-white and milk-white glistening fine nil 10-29' 12 snow-white milk-white glistening fine 10 11.00 ■ Eatimated. > Determined br MIm D. M. Stewart. Minei Branch, Department of Mines. LOT 15, RANGE IX, GRENVILLE TOWNSHIP, MCPHEE PROPERTY. The principal deposit on this property occurs at the extreme north end of the lot. At this point a ridge of magnesite and magnesite-dolomite approximately 1,000 feet long and from 100 to 300 feet wide extends northeasterly along the east shore of Whiterock lake. The physical character and the lime content of samples from the surface of this ridge are given in Table VII, and the proportions of magnesite, magnesite- dolomite, and serpentine contained in the diamond drill cores (drilled by the Harbison-Walker Refractories Company of Pittsburg) are summarized in Table VIII. The sample areas to which the numbers in Table VII refer are shown in outcrop V on Map 1679. The geological relationships of the deposit are shown in Map 1674. Northern Part of Ridge. In the northern part of the ridge there is a total area of approximately 75,000 square feet, of which 10,000 square feet (areas 1 to 53, outcrop V, Map No. 1679) are composed as follows: Magnesite containing less than 12 per cent CaO, 25 per cent. Magnesite-dolomite containing more than 12 per cent CaO, 40 per cent. Serpentine. 35 per cent. 53 In the six diamond drill cores drilled in this part of the ridge (see table VIII) the proportions of magnesite, magnesite-dolomite, and serpentine are as follows: Magnesite, 17 per cent. MaRnesite-dolomite, 57 per cent. Serpentine, 26 per cent. It might be pointed out in this connexion, however, that at least ten additional diamond drill holes would be required before the extent and quality of the material contained in the northern part of the ridge on the McPhee property can be regarded as fully determined. Since the areas on the surface of the ridge from which samples were taken (Nos. 1 to 53) are widely separated, it is probable that the average I percentages of magnesite and magnesite-dolomite obtained in these samples are closer to the percentages actually present (in the upper parts of the ridge at least), than the average obtained from the diamond drill cores. If, in estimating the number of tons of magnesite and magnesite- dolomite present in the northern part of the ridge, therefore, the lower average obtained for each constituent (17 per cent for magnesite and 40 per cent for magnesite-dolomite) be assumed to be present, it is reason- ably certain that the resultant estimates will represent the minimum number of tons actually present. The data from which a minimum estimate can be made follow: Horizontal extent, 75,000 square feet. Proved average depth, 100 feet. Assumed average proportion of magnesite, 15 per cent. Assumed average proportion of magnesite-dolomite, 40 per cent. Number of cubic feet of magnesite and magnesite-dolomite in 1 ton, 12. On the basis of the preceding data it is estimated that 94,000 tons I of magnesite and 250,000 tons of magnesitendolomite are present in the northern part of the McPhee outcrop; but, until a market is procured for the magnesite-dolomite, it is probable that not more than 25,000 tons of the 94,000 tons of magnesits in the above estimate could be profitably mined. Southern Part of Ridge. In the southern part of the outcrop on the McPhee property there is an exposed area of 32,000 square feet, composed approximately as follows (see areas 54 to 135. outcrop V, map No. 1679, and table VII) : Magnesite, 70 per cent. Magnesite-dolomite, 20 fier cent. Serpentine, 10 jwr cent Within this area two diamond drill holes. Nos. 39 and 40, have been drilled. Of these No 39 was drilled to a depth of 180 feet, but No. 40 was started onV" a few fest to the east of an eastward dipping lens of 54 dolomite (see Map 1679 area 97) and in consequence dolomite was encoun- tered at a depth of 15 feet, and after proceeding 9 feet in this material drilling was discontinued. There is, therefore, no information available with regard to the extent of the magnesite on the southern part of the McPhee outcrop at depth except in the vicinity of drill hole 39, and, on this account, the following estimate of tonnage in sight is probably somewhat lower than the actual amount present. On the basis of the usual assumptions the tonnage of magnesite and magnesite-dolomite in sight in the southern part of the McPhee outcrop can be determined from the following data: Adjacent to holt No. >9: Horizontal extent, 5,000 square feet. Proved depth, 200 feet. Asaumed proportion of magnesite, 70 per cent. (Table VIII.) Assumed proportion of magnesite-dolomite, IS per cent. (Table VIII.) Not adjacent to hole No. $9: Horizontal extent, 27,000 square feet. Assumed depth, 50 feet. Assumed proportion of magnesite, 65 per cent. (Titble VIII.) Assumed proportion of magnesite^olomite, IS per cent. (Table VIII.) Number of cubic feet of magnesite and magnesite-dolomite in 1 ton, 12. The number of tons of magnesite and magnesite-dolomite present is, therefore, as follows: Locality Adjacent to hole 39 Portion not adjacent to hole 39 . Toul Magnesite, tons 58,300 73,100 131,400 Magnesite- dolomite, tons 12,500 16^900 29,400 In the southern part of the McPhee property a small mass of magne- site was observed in association with diopside on the west side of the road to the property at a point approximately 300 yards south of the main outcrop, and farther southward on the east side of the road dolomite is exposed for a width of approximately 20 feet. While these occurrences are of interest in that they indicate the possible occurrence of magnesite underlying the clay flat at these points, the material actually exposed is not of sufficient extent to be of commercial importance. A summarized statement of the tonnage of magnesite and magnesite- dolomite known to be present on the McPhee property is as follows: Northern part of outcrop. Southern part of outcrop . Total... Magnesite, tons 94,000 132,400 226,400 Magnesite- dolomite, tons 250,000 29,400 279.400 55 TitUVn. Pkyi€*ICItmu$tr and UmiCoitliwItfStmfltsi^UtitmUt from Mtn-lfOtaennomUl IS.RamtUX, GrtmilU TanuMf. Na Colour LuMre Cimla Percent of cob. MaurU cobbed Percent ofCaO Per cent of CaO In m>. terlal cobbad* I ■f » J 4 S 6 T 1 • 10 II II 11 I 14 IS 16 IT I II l« In » 3) 24 2S 26 27 2S 29 )0 }\ K M H 35 S6-J7 J8 S9 41 42 4j 44 [45 ir-whiu. r-wblte. 'Ute. lowwblle. white now-white, ■oow-whltc. '-white, '-white, white, white. lUatenlnc to dull . lUatenlnf to dull. ■hialag fllMealnf fllMenInf to dull lIlMenIng to dull. lllMenlnf (llMenlnt fUatenlng (llMeniat •white ■white now-white and (pecUed .pSadgrey now-white and grey gllitening and •hlntng gUitenlng and ■hlnlng gUitenlng and dull gllitening and dull ■hlnlng now-white and milk- white irey •hlnlng. duU. . . . white add pink, white white m; v-whlte and pink. . now-white my to white «rey gUetenlng. gUitenlng. dull rey mow-white and pink. milk-whlu and grey milk-white and grey now-white to milk-white gllNening gUetenlng ■hlnlng dull to gllMenlng. duU gUitenlng. ■hlnlni hlnlng :U^teiilng. irey now-white to mUk-whIte ■now-white to milk-white •now-white to milk-white now-white to milk-white •now-white and grey. . arty now-white to cream- white snnw-wUte milk-white and grey . . gUatentng to •hlnlng gUatenlngtoduU. glistening. gll««nlng. gUitenlng. gli^tenUig. glistening, du" uU. gUatening. ■rey and now-white. . irey and maw-white. pey mow-white gUitenlng gUitenlng and duU gUitenlng, ihining, and dull. . . gUiteoing... . gUitenlng and •hlnlng gUitenlng and ihlning line fine medium . . . coandy. . . cryitallbM fine to medium fine to medium fine to medium fine to medium fine to medium fine to medium fine to medium fine to medium fine to medium fine fine fine to medium coane medium fine to medium fine medium to fine fine to medium fine fine medium. . . fine to medium fine fine to medium medium. . . fine medium to fine fine to medium fine. fine. ...... fine medium to fine fine fine fine to medium fine fine to medium fine to medium fine to medium medium . . fine and medium nU 25 nfl aU 2S nU nU nU nU S 2S 4 25 nU nU nU 25 25 nil nil nU nU nil nU nU nil nil nil all 25 nil 50 nU nU 25 nU nU nU nil nil nU nU 30 nU nU dull white magMritc- dolomite duU white magnedte- dolomite grey magnealte-dol- omlte grey magnealte-dol- omlte grey, lerpentlnoui magnedte-dolom- Ite grey, •erpentlnoue magneflte-dolomlte grey, lerpeotlnoua magnewte-dolomlte grey lerpenttnoua doionilte •erpentlDe. grey magneelte- dolorolte grey aerpentli e. grey.^erpentlnoua magnetite-dolomite u.ao> 12.00> 13. 001 15 00> 13 ao> 17 00< 17 78« 10- 261 10. 001 II.QOI U.00> 12-00> t3.00> I2.00> 13.6g> li.Qa> 14.00> t2'00> isao> 11 ao> 12 13" 16 OOi I3.00> 13 59« 15.00> UOQi I6'00> 10. 16* U'00> 13 00> 13 00> 12 ao> 7-76> g.00> 9.oa> IIOOi 13.94« lOOOi 853* 9.ao> ISOO' t2'00> 11 IS* 17 00> I200> 2800 MOB 17. 00 ISOO 16-00 1600 1600 ISOO 16 00 18. 00 56 TaUt Vll.—Conliniud. No. Colour Luttre Grmin Peronit of cob. Material cobbed Percent of CbO 47 48 49 50-SI 52 53 54 SS 56 57 58 «0 «l 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 to 81 82 83 84 85 86 87 88 irey milk-white to grey. •now-white, milk-white and grey cream white, milk-white cream white to milk- white cream-white, medium to Krey cream -white and anow- white cream-white to milk- white and grey cream-white and milk- white cream-white and grey. . . mow-white, milk-white, and grey mow-white to grey gliatening. . . •hining gllMening. . . gliatening glistening and •hining glistening and shining glistening glistening, glistening. snow-white and grey milk-white cream-white and milk- whiu cream-white and milk- white mow-white and grey. . cresun-white and grey . white, milk-white, and grey mow-white to milk-white milk-white glistening glistening and shining glistening glistening, glistening, glistening. snow-white and grey . snow-white and grey. , cieam-whlte to anow- whlte cream-white and mow- white •now-white glistening.. glistening. . glistening., glistening.. glistening. . glistening. glistening, glistening. gUitenlng. glistening. glistening. grey mow-white and milk- white cream-white to gtey snow-white white and grey mow-white, milk-white, and grey cream-white, milk-white, and mow-white snow-white and grey . cream-white, Bnow-white. and milk-white mow-white, milk-white •now-white and milk- white •now-white and milk- white snow-white and milk- white •now-white, milk-white . mow-white and grey. glitteningtodull. glistening fine and medium fine and medium fine to medium granulated fine fine to medium fine to medium fine fine to medium fine fine fine to medium fine to medium fine fine fine and medium fine fine to medium fine and medium fine fine to medium fine, granulated fine medium to coarse fine to medium fine to medium fine fine, fine. glistening gUstening •tuning and dull.. . glistening, glistening. fine fine medium to coarse fine glistening, glistening. glistening... gUstening... glistening. . . glistening. . . I glistening... fine. fine, fine. fine and medium fine fine. fine and medium fine glistening and dull. fine, white nU nil 10 nil nil nil 25 20 15 nil 30 nil nil nil 20 10 nil nU 10 nil nil 10 nil 10 3 5 nil 20 75 nil 25 20 nil 5 10 nil nil 5 nil 20 nil yellow serpentl.ie. . grey magnesite-dol. omite grey serpentlnous raagnesite-dolomite coarse, grey dolom- ite 10<'[. yellow serpentine $% grey, serpentlnous magnesite-dolomlte yellow serpentine .ml grey magneslte dolomite grey magnesite-dol- omlte grey .serpentlnous magnesite-dolomite grey, serpentlnous magnesite-dolomite yellow serpentine . . . coarse, white dolom- ite coarse dolomite 15%, serpentine 5% coarse dolomite. . yellow serpentine. grey magnesite-dol- omite yellow serpentine, yellow serpentine. dull white magneslte dolomite •erpentinelO%, coarse dolomite, 10% 17 00> 1500' U'OOi II 001 10-44> I2'00> llOOi 12'00> 9 00' 000' 13 U0> 9.20" 1000' 900' 8'00> 8'00> 9-97» I0'00> 9'00> 8-00' 14 05> 1100> 9'00> 8 00> 17 27» 8'00> UOO" 700' to 00' 7 00' 1500' 8 00' 900' 800' 800' 6 OC 5'6I' 800' 900' 10 00' 12-23' 57 r*W« Vlt.—Camiiuui. No. ur white, anow-whlte. and grev cream -white, mow-white, and grey white «w-whlte, milk-white. and grey mow-white, milk-white, and cream-white mow-white and grey. . cream white and milk- white ow-white, milk-white, and grey milk-wnlte and grey mow-white mow-white and milk- white mow-white and grey. . mow-white and grey. . mow-white and grey. . mow-white and grey . . mow-white and milk- milk milk-white ^rey grey milk-white gliatening and dull gliatenlng gliMcning and ■hining gliatening gliatening and ihining •liining and dull. . gliatening. gliatening. gliatening gliatening and ahining gliatening gliatening gliatening. gliatening. gliatening . gliatening. gliatening. cream white, anow-white, and grey anow-white anow-white and milk- white anow-white and milk- white mow-white and milk- white milk-white ow-white and milk- white snow-white anow-white and grey . . . . •now-white and milk- white milk-white and grey . .. . anow-white, milk-white, and grey snow-white and grey snow-white, milk white, and grey mow-white 'snow-white Liiatre flne glistening, glistening. glistening glistening, glistening. (listening glistening shining glistening and shining glistening and shining glistening . fine, medium. fine fine and coarse coarse and fine fine. fine. coarse fine and medium fine fine and coarse fine fine. fine and medium fine fine. I glistening. glistening . glistening. glistening. glistening. glistening, glistening, glistening. glistening. glistening. dull and glistening glistening. . . . gliatening . . glistening jgliatening. Grain fine. fine and medium fine and medium fine, fine and medium medium medium . coarse. . . . medium to coarse fine fine and medium medium medium and fine medium fine and medium fine and medium fine fine fine fine and medium fine fine fine and medium fine fine Percent of cob. fine to ' medium > 10 . I J 001 tOOOl 14-00' Ifl'OOi ■JOO' S'OO' 22IIO< 10 no' 6 00> 9 oil' 6.07> 7 00' 10 00' 7 SO' 8 DO' lOOOi 12.001 <) 00' Q 491 9 00' II 001 25 001 «.84> 6 071 .1 W 7 001 « 001 to 001 10 mv 10 00> « 00' 1 00' 10 00' 11 0(1' 10 0(1' t(s no' iino' 10 00' 9 001 Per cent of CaO in ma- terial cobbed' IHOO 14 00 14 no 58 TMt ^'''■J'f^l^ry DtHription of Diamond DnU Cores from Uatnt»k Dtpoul OH Lot 15, Rante IX, GrtnvtlU Township.* No. of hole Magnetite containing leu than 12 per cent CaO. feet Average CaO content of niagneaite MiiKnesitc- dolomite containing more than 12 per cent CaO. feet Serpen- tine, feet Total depth of hole, feet 34 35 36 37 38 39 40 23 21 9 9 15 15 1404 15 909 10-48 9-6() 11-47 10-80 9-95 7- 40 7-33 86 53 28 .)() 35 79 'I' 31 10 43 46 7 A 7 ■ 140 85 80 85 57 100 180 24 The magncsitc is mined at the McPhee property as elsewhere in the district by the open-cut methfxl. The magnesite i.s cobbetl as broken down at the pit's face and loaded directly into wagons (or sleighs in winter) and the waste rock is carted to the dumps. Jhe equipment on the property includes a 10-ton keystone kiln, four retort furnaces, a mill for grinding the calcined magnesite. a cable- way for hoisting the ore into the kiln (Plate X), a number of boilers, steam drills, pumps, and other machinery necessary for quarrying operations. Camp buildings having accommodation for 100 men have been erected on the property and a road 1 1 miles in length has been constructed from the magnesite deposit to the Canadian Pacific railway at Calumet. LOT 13, R.\NGE IX, (iRENVlLLE TOWNSHIP. The southern part of this lot is txcupied by a high ridge of garnet and granite gneiss on the northern slope of which, adjoining the clay flat which extends along Magnesite creek, outcrops of dolomite are exposed. One of these deposits, situated on the vast side of the lot about 200 feet to the north of the road crossing the property, is approximately 40 feci long and 20 feet wide; and another tx-curring about 100 yards farther down the hill to the northwest is exposed for 30 feet in the bottom of a trench. The dolomite contained in these deposits is a coarsely crystal- line white variety containing disseminated grains of wax yellow serpentine and flakes of graphite. Sin-e dolomite has lifjo or no commercial value, these deposits are of importance at the present time only in so far as the\ indicate the possible occurrence of magnesite in their vicinity. If, in the future, a market for dolomite should be procured, they might bee, . valuable; but additional development work would be required to pre. their extent. > Analywt by J. T. DnnsM and Co.. Montreal. 59 LOT 16, RANGE IX, GRENVllXE TOWNSHIP. This lot lies on the eastern margin of a batholithic mass of granite gneiss and, except at points along its eastern boundary where embay- ments in the Iwtholithic margin occupied by rocks of the Grenville series occur, is entirely underlain by gneiss. The most extensive area of rocks belonging to the Grenville series, on the projicrty, underlies a drift covered depression at the southeast comer of the lot and it is in association with these rocks that a mas-s of dolomite and magnesite- dolomite has been discovered. At the time the property was examined by the writer in August, 1916, the only indications of magnesite at this point were a few large boulders of magnesite in the drift and a northeasterly trending ledge of quartzite and diopside alx)ut 3 feet wide and 20 feet long, exposed in the bed of a small creek. There was a parallel, drift-covered ridge about 40 feet wide and 300 feet long adjoining this outcrop on the southeast, however, which had the elliptical form and conformable trend common to all the magnesite deposits. A pit was excavated in the drift by Messrs. Fitzsimmons and Boshart with the result that a deposit of magnesite- dolomite and dolcr'.te containing included masses of diopside was disclosed. When the deposit was visited by the writer in January, 1917, a pit approximately 30 feet square had been excavated, the bottom ol which was underlain entirely by this material, but up to that time no No. 1 magnesite had been discovered. LOT 11, RANGE VIII, NORTH, GRENVILLE TOWNSHIP, CAMPBELL PROPERTY. At a distance of 100 feet to the north of the road which crosses the south end of this lot a dolomitic magnesite was exposed along the whole length of the bottom of a 50-foot trench. This dolomitic magnesite is a medium-grained, uniform, white, crystalline material containing dis- seminated grains of wax-yellow serpentine. The lime content of the dolomitic magnesite has not been determined chemically, but the physical character indicates that it probably contains at least 20 per cent. LOT 12, RANGE VIII, NORTH, GRENVILLE TOWNSHIP. The deposit of inagnesite-dolomite on lot 12, range VIII north, Grenville township, consists of a group of large boulders situated near the south end of the lot at a point a few hundred feet east of Calumet creek and about 400 feet northwest of the dolomitic magnesite exposed in the bottom of a trench on lot 11. Whether the boulders comprising this deposit have been derived from the underlying bedrock cannot be positively determined, but their similarity to the bedrock a few hundred feet eastward indicates that such is possibly the case. CO A sample of the boulder material, collected by R. L. Broadbent, wa« analysed by R. A. A. Johnston of the Geological Survey with the following result: Magnwium carbonate 66 M per c»m Calcium carbonate 23-96 " Magneaia in other form than carbonate 4M * LOT 11, RANGE VIII, SOUTH, GRENVILLE TOWNSHIP. Dolomitic magnesite is exposed in the bottoms of a pit 25 feet square and a trench 20 fett long, on the western slope of a drift covered ridge, near the northwest comer of this lot, and about 200 yards south of the dolomitic magnesite exposed in the bottom of trench on the Camp- bell property. The material exposed at these points is similar in every respect to the dolomitic magnesite found on the adjoining Campbell property and indicates that there is possibly a very extensive area of this material in that locality. LOT 12, RANGE VIII, SOUTH, GRENVILLE TOWNSHIP. An enormous boulder of fine, white glistening magnesite also occurs on lot 12, southwest of the exposure on lot 11, and about 200 feet west of Calumet creek. The larger part of the boulder is buried in clay and sand so that neither its whole extent nor its relationships to the under- lying bedrock have been determined. A shipment of 52 tons of magnesite derived from this boulder was made by Messrs. Fitzsimmons and Boshart during the summer of 1916. LOT 9, RANGE XI, AUGMENT.XTION OF GRENVILLE. Serpentinized dolomitic magnesite occurs on this lot on the east shore of Papineau or Commandant lake. At the point examined by the writer the dolomitic material formed a low point about 100 to 200 feet wide and several hundred feet long projecting northward between a small bay and the main expanse of the lake. An average sample collected by the writer from the deposit and analysed by H. A. Leverin of the Mines Branch had the following composition. CaCoi 36-60 MgCOi 63-66 Jnsol 0-10 Toul 100-36 A deposit of similar material was reported to occur inland from tht lake, but was not examined by the writer. LOT 21, lANGE I, HARMNOTON TOWNSHIP. Near the north end nf this lot a triangular shaped mass of crystalline limestone belonging to the GrenvilU; series projects into Rouge river forming what is generally known as Marble rapid. On the west the limestone adjoins a ridge of Grcnvillc quartzite and along this contact there is a highwater channel so that the limestone masst becomes an island during periods of flood. This insular mass of limestone has an approximate length of 2S0 feet and a width of 100 feet. It consists of medium-grained, crystalline limestone containing disseminated grains of wax yellow and reddish brown serpentine, and numerous nodular or lenticular masses of serpen- tine and coarse white dolomite. At one point an included mass of cry- stalline porous calcite was also observed. The disseminated serpentine is concentrated in bands which trend in a northeasterly direction and dip to the northwest thus conforming in their strike and dip to the structure of the adjoining quartzite. Near the north end of the mass a crumpled lens of graphitic coarse, white dolomite about 12 feet long was observed to be enclosed in banded limestone, the crumplings in which conformed to the plications in the dolomite mass, thus indicating clearly that the present form of the dolomite mass has resulted from deformation. As far as was observed there is no magnesite in this locality and the amount of dolomite present is very limited. The deposit is of interest, however, in that its lenticular and banded structure is strikingly similar to that of the principal magnesite deposits of the district. LOT 7, RANGE X, GRENVILLE TOWNSHIP. Magnesite in place was not observed on this lot, but a number of boulders of fine glistening white magnesite of excellent quality occur near the north end of the property, which are of interest because they indicate the presence of an undiscovered deposit of magnesite in the district. In the Grenville region the direction of glacial movement was approxi- mately from north to south so that all boulders of magnesite which have been transported are found south of the deposit from which they were derived. It is obvious, therefore, that the boulders found on lot 7, range X, Grenville township, have not been derived from any of the known deposits in the district, but from an undiscovered deposit occurring either at the no^th end of lot 7 or northward in the direction of Green lake. :1 ■i •1 CHAPTER V. SUMMARY AND CONCLUSIONS. Some of the more important results of the study of the character, extent, and relationships of the Grenville magnesitc deposits briefly stated are as follows: The deposits are of early Pre-Cambrian age and occur in association with the metamorphosed group of sediments (crystalline limestone, sillimanite-garnet gneiss, and quartzite) known as the Grenville series. All of the deposits so far discovered in the district occur in the major valleys in which stratified marine clay and sand have been deposited. Through this material the deposits outcrop in ridges or groups of ridges up to 1,000 feet in length and 300 feet in width. The ridges in which the magnesite is found are composed mainly of magnesite, dolomite, serpentine, and diopside. The proportion of magne- site free from dolomite or dolomite free from magnesite in the deposits, however, is small, these minerals occurring for ihe most part intimately intermingled in varying pro(X)rtion8. The deposits have all been so intensely deformed since their for- mation that masses of serpentine, dolomite, anil other variations which they contain have been squeezed out into lenses. The study of the charactei^and relationships of the deposits has letl to the conclusion that they are of metamorphic origin, and have been formed by the replacement of the limestone member of the Grenville series through the agency of magnesia-rich solutions. While the magnesite everywhere includes more or less dolomite, diamond drilling and other development work have shown that extensive masses of magnesite are present in which the lime content resulting from the presence of the dolomite averages from 7 to 10 per cent. A summarized statement of the number of tons of magnesite and magnesite-dolomite in sight in the various properties is as follows:' — — Magnesite (ontain- .Magnesite-dolomite ing lew than 12 per containing more than Property cent CaO, 12 per cent CaO, tons tons Lot 13, range I, Harrington township. . . . 25,001) 8,000 Lot 18, range XI, Clrenville township. . . . 15.000 6,000 Lot 15, range XI, Grenville township. . . . 418,000 186,300 Lot 1.S, range X, Grenville township 2.500 4,000 Lot 15, range IX, Grenville township. . . 226.400 279,400 Total 686,900 . _ 483,700 > It miut be noted in thii conn«don that th«w pRimatn nave no definite rrlatioiuhlp t» the amount of ma«nt»it* presrai on the various propotles siiKe some deiKWit! have been mon eReorively derel ui) e«1 by diantond drilling and other development operation*. 63 Of thr alKJve lotal, however, th«T»' in iippruxiinau-ly 69,(XH) tonf* of magnesitr on lot 15. range IX. ami KMMK) tons on lot 15, range XI, that could not be profitaWy mined unk-w a niurkit for niaKni-Hitc-dolomite wd» procuri-d. Since thw niagnesite and nwiKncsite-ikilomitc arc. on the whole, ki* rf««i»tanl tn iroeion ihan either the serpentine or the rmks of the (Iren- ville Hcries with which the deposits are awtociatitl, it is probable that the outcrops in whi< h the ru.(>;iiei»ite incurs have little or no reiationship to the actual di8trilnitk)n of the inaKnesite and ih.it extensive mattscs of magnefiite ocr magnesii no the valleys, and especially those valleys where limestone and oth-r inemU-rs of the Grenville scries are known to be pres«-nt. The occurrence of boukU-rs of maKuesite in kKalities where they could not possibly have been derivetl from the knnv^n occurrences of the material indicate* that there are other undiscovend dt-positsof m.ignesite in the diiitrict. 6S } fu ± ..^'-.u. u.-iun (,<> 7.« ^^€^f..".J 75 I'lMf Ml. (iilrini'd (irrMvillv ni.iiii ■■'*itr-itr: liulil, (luliiniili' naliinil »i/i-. i I'aKi- 2f> i M. (alrincd (.rrnvillr iii.iuiusiir, shiiwinn iiiiliisions of ilolomili-. i I'ani- !<>.> MOOCOTY RESOIUTION TKT CHART (ANSI ond ISO TEST CHART No. 2) 1.0 tiiUiS 12.5 i 1^ Ih |2.2 I.I K m jS /APPLIED IM/IGE ^^ t65i East Main Street ■TjS Rochtster, New York 14609 USA ^ (716) 482 - OJOO - Phone ^ (716) 28a-r9B9-Fa> I'LATK VIM. Calcined C.renville maKnesite-doloniite: dark, niagntsitc; light, dolomito; l)latk s|)ots, sfriK-ntint; enlarged two diameters, i I'age 26.) Crcnville niagncsite-doloniitc calcined in a reducing atmosphere; enlarged two diameters. (Page .16 ) 7'> X 81 ss INDEX. Anal^t Pace 31 21 11 10 IS 5 16 38 Ad«m»jF. D ^""?'''TS(CaUfomi.nii«|ne«u: •• • Gredan magiietiw. . . •_ - „ • hydromtgnetite from Atlin, ».«. . magn^U ^^J^^^ft river. B.ci .'.:: : : : : SSjburutcrop. .i;.V5.r«.,.ix;Gr.nviUetp. « tp 5 • sUe. StMl Company of Canada . . 9 - ty^cal Austro-Hungaran magnwiU jl Augm.^nt*^iion of Grenville. lot 9. range XI i, 8. 30 Austria-Hungary magne»lte Apatite Barlow, A. E Basal complex Bolton tp., Que Boshart, W. P . „ >. Bridge River di^lru'., UX. . British Columbia magn'-Mte Broadbent, R. L Buckingham senes 19 U . 17, 59. 60 15 3. 14 17, 39, 60 20 Calcination Calcite Californian magnesUe Campbell property. _ __^^ Canadian Magnesjte Company. • magnesite deposits. Carbon dioxide, manufacture of Caribou road. B.C Caustic calcined magnesite Chalcopyrite. .. Cold water paint Commandant lake Crude magnesite 35 21 .1,3.11.30 17 6 U 4 21 7 60 4 Daly. R. A Dead burned magnesite Deformation Diabase Diopside ■ .; Distribution of magnesite. Dobbie mine Dolomite ■• Donald. J. T. and Company. 31 4 27 22 28 25 37 25. 26. 28 38 DriU Drywkic, Pam • i^gnwiM (teporiu on lot IS. rue* XI. CrmviU* tp 10 d»le,C.W " EpM>m-Mlt Fitnimmo.'^, Mr u Fluorite S! Frechette, H j Fution poim a. u Gcrmanien creek, C C ia <-i..:.i •• Glacial Granite S ' •lyenitc gneii* S Graphite ;' ,. mm Grecian magnerite ■»••«.'*" Grenville Lumber Company IL •erie*. .. ■" * township lot 7, range X. . 13. ' IX. - IX. X. 15, 15. 15. 16. 18. XI IX XI as 61 ss sa 51 41 » JO. J»» m Grosvenor, W. M ,. . • Gwillim, J. C "■ " Harbison-Walker Refractonef **' 5! Harrington township ■ .. " lor 13, range I *' •21, • I •• Hayes, A. O ,i' ' ' ..i ' js ' J If History of magnesite mining in Grenville district I. Illecillewaet, B.C 14 lllecillewaM, a.y. ,» International Magnesite Company Johnston, R. A. A. L. 60 14 Uc des Mille Ucs, Ont J| Lenticular form ^ Lcverin, H. A ^ Lime content 21 I.ogan. W., Sir " McAlllrter.W.B McConMll, R.G McPhM, D propwty M»r<«*it*> crytulUn* • inlawakify ol . MuMiium carboMrt. Ughl • chlorldt • mtUkllic • kulphkU Maiixt't* M«rble«pid.^ •■• Marine cUy and MiMl Melkman.S Metamorphic pyrowmU. Mkrocline Mineraiofy N. New Brunswick tfff^;- ViL^llny North American M«P«f»'" S^JfvTil « Grenville tp., lot li> f*"!* vill" « « -I • 12, range Vill. Nova Scotia magne*'" j. : >;;rjJ ' " ' • • Stf«l and Coal CompMiy- • Pam IT 14 » S s It I I 1 I » «1 M IT 31 ]1 28 14 17 59 59 16 16 Ontario magnetite. Orangedale, N.S. . Origin Oxych'oride 14 16 30 6 Paicoioic Papineau lake Phlogopite.. Pleistocene Pre-Camb.-ian mtni^vM Prehnite ■ ; ■ _ Preparation of magnesiie. . . ■ ■ „ ; ' 11_^, Production of magnesite in Aurtna-HunB»0' 11 • « • Greece , • • • United Sutea. . Properties, description of « list of Pyrite Pyroxene *0 21. 4 10 16 10 12 37 37 21. 27, 29 21 Quartz • syenite « • porphyry. Quebec magnesite 21,.^ 22 22 14 88 *• Paci 34 Redlich, Mr '.'.'.'.'.'.'.'.'.'.'.'■'■■'■'■'■'■ * Reftactory material 32 Replacement of limeitone 15 Robertson, W. F S. 21 Scapolite .•■.:, 17, 52 Scottish Canadian MagneMte Compwiy 28 « • property 31 Sedimentary deposition 25, 28 Serpentine ; 30 " decomposition of 25, 38 Shaw mine ,• • ■ 7 Shawinigan Electrometals Company 6 Soiel cement 8 Sources of supply, foreipj .. . •• ■ •• -j 60 South Grenvilie township, lot 12, range VIII 29 Sphalerite 7, 8 Stassfurt salts • 5 Steel Company of Canada 52 Stewart, D. M 26 Structure 26 " banded 62 Summary and conclusions 14 Sutton tp., Que 22 Syenite T. 19 Table of formations 29 Talc '.".'.'.'.'. 34 Tests for lime 26 " magnesite 21 ' Titanite ^1 Tourmaline 14, 16 Turner, N. L U. 10 United States magnesite 4 Uses of t.agnesite 8 ■ miscellaneous W. Wait, F. G Watters, T. J . West Beach, N.B V^^l^lp by^he'auiphite procMi,' manufacture of. Y. Young, G. A. . . . . • Yukon, magnesite. 17 17 14 52 6 IS 14 Zinc blende. 27 GeoJogicaJ Survey, Canada. . Dta^rajm showing magnesitfi deposits, Lots 15, ranges IX and X, OremHletemnship./lrgvitsuH < ScaJe <^f«et To ».{xotnf»ny Memoir by III C W>ison . aLtaJogue No 1674 Rmprint Legend ChannplaJn epoch L Marine day and sand 6/a.ciaJ Bouldery drift 5uc/aniham series Grenville series .^ Pyroxene syeniUf Magnesite, ma^nesite - dolomite and serpentine Quartzite ^r' VerticaJ straXa. |72V- Dip and strike ^ Strike C^T^ /'/to 'm,^^ Dumps Tramways I ••♦» Diamond drill holes omits, 'enteuH courrt^, Queboc. >tcaf Stirv^, CantS" Dfm^rajn shamnf ma^jrtmitile ■ lot IS. fmnfeX/, Granvith tawnaNp , j^r^wtteuit Sca^ oT rmit -•ovy Umrnoir iy tt I W _^ tf {1=3^ y Mm |«*aM««c ^S^NtUlV •i*-^ Gwoloff'mj 'iur-^my. r,a/-*«tf« /o lu.tampxny Memoir by kl C Wilson Diagram showing ma^nes/te outcrops in Grenville torn V .... 9 5c't./e of fe^t y , mm 'ille township. /Irgenteuil county, Quebec. rert y ^ ^ \ ■' iKgfItU r_j ^ot M Jvht /f I " ^ Ca,ta.lo/^u€ No /679