I; 81,1‘ N W
UNIVERSITY OF VIRGINIA PUBLICATIONS
B 478001
BULLETIN
OF THE
PHILOSOPHICAL SOCIET Y
Scientific Series, Vol. I, No. 7, pp. 200-221, January, 1912
A Contribution to the Geology and Mineralogy of Graves
Mountain, Georgia
B Y
THOMAS L. “"ATSON AND J. \VILBUR VVATSON
U'NI"ERSITY OF VIRGINIA
Charlottes"ille,Virginia, U. A.
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UNIVERSITY OF VIRGINIA PUBLICATIONS
BULLETIN OF THE PHILOSOPHICAL SOCIETY
SCIENTIFIC SECTION
Vol. I, No. 7, pp. 201-221 January, 1912

A CONTRIBUTION TO THE GEOLOGY AND MIN ERALOGY OF
GRAVES MOUNTAIN, GEORGIA.*
BY
THOMAS L. AND J. WILBUR WATSON.
INTRODUCTION.
To the mineralogist, Graves Mountain, Georgia, has long been known
for the occurrence of an interesting association of rather uncommon min-
erals. Knowledge of the occurrence of the interesting group of minerals
at this locality was first made known in a published paper by Professor
Charles U. Shepard in 1859. Since the appearance of Professor Shepard’s
paper in 1859 practically no work, based on field study of the mountain
proper, has been published, although the literature contains many refer-
ences to the description of mineral specimens from this locality.
Very little is known of the geology of the immediate area within which
Graves Mountain is located. Mining for gold and copper three and one-
(Q half miles north, and for gold ten miles south, of the mountain has been
engaged in at frequent intervals since the early 50’s. Detailed field studies
have not extended beyond the limits of the mines and no maps of any
description have been attempted for this part of Georgia. Within recent
years several geologists have recorded the results of their studies of the
metal mines but the intervening area, more especially that of Graves Moun-
tain and the immediate vicinity, still remains for detailed study and map-
ping. '
The description of the geology of Graves Mountain briefly summarized
in this paper is based on several short visits to the area by the senior author
since 1900. The last visit was made in March 1911, when a collection of
the rocks and minerals was made for laboratory study. The chief object
*Read before the Scientific Section, February 5, 1912.
201 I
202 UNIVERSITY or VIRGINIA PUBLICATIONS
of this paper is to record _the results of field and laboratory (chemical and
microscopical) studies,pf'ar'r interesting area that has long been"known to
the mineralogist but pijacticafly neglected by the geologist. The chemical
analyses of the speciméns collected are the work of the junior author.
GENERAL GEOLOGY.
Location. Graves Mountain lies in the extreme western part of Lin-
coln County, Georgia, within less than a mile of the Wilkes County bound-
ary; ten miles nearly east from Washington, the county seat of Wilkes






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_FIG. 1. MAP OF MIDDLE NORTHEAST GEORGIA SHOWING LOCATION OF GRAVES
MOUNTAIN IN LINCOLN COUNTY.
County; six miles southwest of Lincolnton; and about forty miles north-
west of Augusta (map, fig. 1). It is within but near the eastern border of
the Piedmont Plateau province, a short distance north of the fall line, which
marks the passage of the plateau crystalline rocks beneath the Coastal
Plain sediments. The area forms a part of the central divide region be-
tween the tributaries of Little River on the south and southeast and those
of the Savannah River on the east and north. Little River is distant about
eight miles south of the mountain and is the nearest stream of large size.
GEOLOGY or GRAVES MOUNTAIN 203
Physiography. The immediate country in the vicinity of Graves Moun-
tain averages about 550 feet above tide. It has gently inclined but broadly
undulating surfaces so characteristic of the inner eastern margin of the
Piedmont province. The larger streams have carved deep valleys below
the plateau surface.
Graves Mountain is a conspicuous ridge (monadnock) of unreduced
hard rock, which rises to an altitude of 700 feet above tide level, and several
hundred feet above the Piedmont Tertiary base-leveled plain. It is the
highest point of land between it and the ocean. It is removed from the
major lines of drainage, which fact together with structure and lithologic
character of the rock of which it is composed, are the chief factors responsi-
ble for its existence. A number of similar low ridges, locally called moun-



ya ya.

_ I" *~ ‘Wo.-<.-H";-
sW..__\~ ~ --M. . W.


FIG. 2. VIEW OF GRAVES MOUNTAIN, GEORGIA, LOOKING SOUTHEAST. (SKETCH BY
J. H. WATKINS, FROM PHOTOGRAPH.)
tains, stand up above the general level of the plateau surface over parts
of Lincoln County, but none of these are found in the immediate vicinity
of Graves Mountain.
The ridge, locally known as Graves Mountain, has a length of two miles
along an approximate northeast-southwest direction, coincident with the
general structure of the rocks of the area, is less than a half mile in average
width, and rises several hundred (300?) feet above the surface of the sur-
rounding plain. The slopes of the mountain are very unequal. They are
less steep on the northwest side which is the direction of dip than on the
southeast side. They are steeper near the top of the ridge but become more
gradual about half the distance down until merged with the plateau sur-
face at the base. The upper portion of the ridge is greatly scarred and
roughened from weathering and low and high cliffs are numerous. Fig. 2,
a pen sketch from a photograph taken from a position looking southeast,
204 UNIVERSITY OF VIRGINIA PUBLICATIONS
shows the outline of the mountain. On the crest of the ridge, a fairly pro-
nounced axial depression or sag is noted bounded at either end by higher
elevations or peaks which slope away somewhat gradually toward the north-
east and southwest until merged into the plateau surface.
Geology of the surrounding areas. The rocks of the region are strongly
foliated metamorphosed crystallines of two dominant types,* variable
micaceous schists and gneisses. To the north and south of Graves Moun-
tain the schists vary from' biotitic to sericitic, and in places are highly
quartzitic, feldspar being only sparingly developed and is frequently absent.
The gneiss of Little River basin in the vicinity of the gold mines in northern
McDuffie County is of granitic composition, usually carrying biotite as the
dark silicate mineral, although hornblende has been noted. The dominant
rock of the gold belt on Little River is mica schist which encloses the gold
veins of milky white quartz containing the sulphides, pyrite, chalcopyrite',
and galena. The gneiss of this belt is derived from an original granite and
Jones suggests that because of chemical similarity the schists are also of
probable igneous origin. Analyses of these rocks are given in columns IV,
V, and VI of the table of analyses on page 205.
The geology of the Seminole copper mine and immediate vicinity, three
and one-half miles north of Graves Mountain, is more varied, several igneous
rock types occurring that have not been observed in the Little River belt on
the south. In addition to the mica schists, schistose quartz-albite porphyry
occurs, composed of a fine-grained groundmass of quartz and plagioclase
feldspar intimately intergrown and exhibiting spherulitic structure, through
which are distributed phenocrysts of opalescent quartz, some albite and
* During the field season of 1911, Mr. Otto Veatch of the Georgia Geological Survey
made a brief reconnaissance over much of Lincoln County and contiguous parts of
the counties to the south. In a personal communication to the senior author, Mr.
Veatch states that the belt of metamorphic sedimentary rocks in which Graves
Mountain is located seems to extend from the Savannah River in Lincoln County
westward to Graves Mountain and Adasburg a short distance south in Wilkes County;
thence southwestward through the northern part of McDuffie and Warren counties.
A generalized section extending from Lincolnton southeastward to Augusta, a dis-
tance of nearly forty miles, prepared by Veatch shows the principalrock types of the
area to be schists, slates, and quartzites with an extensive area of granite containing
intrusions of serpentine,peridotite and diorite, occupying the central portion of the
section. The metamorphic sediments on the northwest side of the granite area dip
steeply toward the northwest becoming vertical with slight southeastward inclina-
tion near and at Lincolnton. From the southeast margin of the granite to Au-
gusta the metamorphic sediments are steeply inclined to the southeast. As indicated
in Veatch’s section the metamorphic sediments dip steeply away from the granite
on the northwest and southeast sides.
GEOLOGY OF GRAVE~S MOUNTAIN 205
biotite.’ Numerous dikes of basic igneous rocks, mainly diabasic in charac-
ter, ranging up to several hundred feet in width, occur. They are clearly
intrusive in character since they cut across the foliation of the schists irregu-
larly. Likewise the sulphide ore bodies (chalcopyrite, galena, sphalerite,
and pyrite) developed in a shear zone in the sericite schists approximating
a northeast-southwest direction and crossing at a small angle the schistos-
ity, are cut across and‘ faulted by some of the dikes of basic rock. The
rocks are cut by numerous joints and in places by faults. Columns I,
II, and III in the table of analyses below show the composition of some
of the rocks near the Seminole mine.
The rocks of the region are deeply decomposed by atmospheric agencies
so that relatively few exposures are seen. They are strongly foliated, the
general direction of strike being northeast-southwest, with local variation
observed from place to place. At Graves Mountain and further northward
at the Seminole mine the dip is to the northwest. Southeastward from
Graves Mountain about six miles, at Amity Postoffice, and thence south-
ward to Little River the schists likewise dip to the northwest.*
Analyses of porphyry, gneiss, and schist, Lincoln and McDu-jfie Counties, Georgz'a.j
(Dr. Edgar Everhart, analyst).




I ‘ II III 1 IV V VI
S102 . . . . . . . . . . . . . . . . . . . . .. 68.07 I 68.13 69.30 ’ 63.82 62.45 61.25
A12o......................, 15.07 17.49 15.91 15.94 15.91 17.18
1.13 1.19 3.20‘! 2.91 2.07 4.49
F50 . . . . . . . . . . . . . . . . . . . . 3.42 § 1.38 0.18 ! 3.87 3.80 2.54
MgO . . . . . . . . . . . . . . . . . . . 2.27 3 1.00 0.21 1.20 1.76 Q 2.21
0.73 0.75 5.92 I 2.91 3.70 3.78
6.06 1 3.50 3.35 2.54 2.33 2.50
K20 . . . . . . . . . . . . . . . . . . . . .., 0.29 i 3.00 0.14 1.80 0.40 1.60
Ignition . . . . . . . . . . . . . . . . 1.25 ' 2.06 1.80 3.70 5.41 3.03
H20(100°o.).............. 0.01 l 0.03 0.52 0.06 0.03 0.01
0.37 I 0.74 0.48 055 0.82 0.92
trace trace none 1 0.04 0.13 0.02
S . . . . . . . . . . . . . . . . . . . . . .. 1.1-1 4 0.22 0.03 trace I 0.22 0.24
M10 . . . . . . . . . . . . . . . . . . . 0.31 I 0.30 0.11 0.18 l 0.37 0.27
(302 . . . . . . . . . . . . . . . . . . . . .. ,1 0.21 0.50
Total...................|100.12 ’ 99.79 101.15 99.73 ‘ 99.90 100.04

* Veatch, Otto. Personal communication, January, 1912.
T Jones, S. P., Bull. 19, Ga. Geol. Survey, 1909, pp. 55-62.
206 UNIVERSITY or VIRGINIA PUBLICATIONS
I. Quartz-albite porphyry, near Seminole copper mine, Lincoln County, Georgia.
Phenocrysts of quartz, albite, and biotite in a fine-grained groundmass of
quartz and plagioclase feldspar with accessory-magnetite, apatite, and pyrite.
Coarse spherulitic structure shown in groundmass in places.
II. Schistose and altered quartz-albite porphyry, same locality as I. Same as I
except that sericite developed from metamorphism. ‘
III. Granite porphyry, 1 mile east of Seminole mine. Rock is considerably altered.
Mineral composition essentially the same as I and II. Some biotite and
much epidote present.
IV. Biotite gneiss-, Bell shaft, Columbia gold mine, McDufi‘.ie County, Georgia.
Contains feldspar (plagioclase and orthoclase), quartz, and biotite, with
accessory magnetite and secondary chlorite, muscovite, and calcite.
V. Mica schist, Columbia gold mine, McDuflie County, Georgia. Contains quartz
and sericite, with some plagioclase feldspar, chlorite, calcite, and pyrite partly
altered to iron oxide. -
VI. Mica schist, Parks gold mine, McDuffie County, Georgia. Composition same as
V except that mica is less abundant and much epidote is present.
The norms of the rocks represented by the analyses in columns I,
II, III, and IV‘ are as follows:
Norms of quartz-albite prophyry (I and II), granite porphyry (III), and gneiss (IV),
Lincoln and McDufiie Counties, Georgia.




I I II III IV
0 A . _
Quartz. . . . . . . . . . . . . . . . . . . . . .' 25.68 32.88 36.36 34.32
Orthoclase...................... 1.67 17.79 0.56 10.56
Albite . . . . . . . . . . . . . . . . . . . . . . . . .. 51.35 29.34 28.82 20.96
Anorthite....................... 3.61 3.89 27.52 10.56
Corundum . . . . . . . . . . . . . . . . . . . . .. 3.47 7.14 0.10 6.02
Hypersthene.................... 7.98 3.29 _ 1.02 7.09
Hematite . . . . . . . . . . . . . . . . . . . .. 3_2()
Ilmenite . . . . . . . . . . . . . . . . . . . . . . .. 0.76 1.37
Magnetite . . . . . . . . . . . . . . . . . . . . .. 1.62 1.86 4.18
Titanite . . . . . . . . . . . . . . . . . . . . . . . . 1 . 18 .
Pyrite . . . . . . . . . . . . . . . . . . . . . . . . 2.04 0.36 L I
Apatite.........................1 ; O_g3
Calcite . . . . . . . . . . . . . . . . . . . . . . . .. 0,50
I120 . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.26 2.09 , 2.32 3.76
99 .44 99. 62 101.08 100.09


The position of the rocks i11 the quantitative classification of igneous
rocks may be summarized as follows:
GEOLOGY or GRAVES MOUNTAIN 207

NO. SYMBOL NAME
I I—II.4.1.5 Persodic pantellerase; no subrang name. I
II 1 .3 (4) .2 . 4 Alsbachose-lassenose.
III I.3(4) .4.3 No name.
IV II.3.3.4 Sitkose.


* Classed as of II.
Geology of Graves ll/Iou'ntain; The rock composing Graves Mountain
which, as indicated on the map, fig. 1, lies between the group of gold mines
along Little River and the Seminole mine but nearer the latter, is a fine-
grained quartzite. It varies from moderately thinly foliated to essentially
massive in structure. Its position is along the northwest margin of a
metamorphic sedimentary series of crystalline rocks. The dip of the quart-
zite is toward the northwest at a variable angle and the strike is north-
northeast. N o igneous rocks have been observed at Graves Mountain but
acid and basic intrusions occur at other localities within the general area
as described above. The basal portion of the mountain and for some dis-
tance up the slope on the northwest side the rock is the foliated variety
quartzite-schist, while the crest and for an undetermined distance down the
slopes the rock is massive quartzite, with only a tendency to schistosity
indicated. This latter phase (massive) of the quartzite has been designated
by Shepard* the rather rare variety known as itacolumite. On top of the
mountain the quartzite is cut by quartz veins, some of the larger ones of
which measure several feet in thickness) These do not appear to have been
crushed or brecciated and are apparently barren. Smaller quartz veins
only a few inches wide contain rutile and iron oxide. The rock from some
of the small openings shows fracturing and brecciation.
The quartzite schist is light in color when fresh but is very generally
discolored at the surface some shade of red by iron oxide. from weathering.
It is composed of quartz and less sericite as the essential minerals, with
cyanite and occasional small grains of rutile and black oxide of iron as the
principal accessory minerals. A partial chemical analysis of this rock gave
SiO2 79.18 per cent; A1203, 14.14 per cent; and Fe2O3, 3.17 per cent.
Under the microscope thin sections of the rock show a fine-grained
mosaic of angular quartz, colorless mica (sericite), stout columnar crystals
of colorless cyanite with frayed out and ragged ends, usually partly altered
to muscovite and red oxide of iron, and frequently containing inclusions of
rutile and quartz. In some cases the iron oxide obscures much of the cyan-
*Shepard, Chas. U., Amer. Journ. Sci., 1859, vol.‘ 27.
208 UNIVERSITY OF VIRGINIA PUBLICATIONS
ite substance and is formed along the cleavage and fracture directions of
the mineral. Alteration of cyanite to muscovite is apparent in the hand
specimens. The quartz frequently shows optical disturbance and contains
inclusions of rutile and other substances of an indeterminate character.
Small granules of black oxide of iron, probably magnetite, are usually pres-
ent, and more or less red oxide of iron is present in all the thin sections.
Rutile, as euhedral and anhedral crystals and nonpleochroic, is formed along
the boundaries of the quartz grains and as inclusions in the quartz and
cyanite.
The massive quartzite which occurs on the crest and higher slopes of the
mountain, has essentially the same composition as the quartzite schist.
It is compact in texture and lightnearly white in color when fresh, but near
the surface it is friable easily crumbling into a loose sand under pressure
of the hand, and is a buff color, due to the presence of some iron oxide. It
is fine-grained in texture, composed largely of fine sugary quartz, some
muscovite, and in places contains abundant large and small tables of cyanite
of pale green color when fresh, crystals of blue lazulite, and small grains of
red rutile. Pyrophyllite is rather common. Cyanite, lazulite, and rutile
are usually intimately associated, the first two (cyanite and lazulite) are
frequently embedded one in the other, and the rutile occurs as separate
grains and as inclusions in the other minerals. The weathered surface of
the rock is quite rough and, when examined in detail, the more resistant
minerals, lazulite and cyanite, stand out in moderate relief. Alteration
of the columnar crystals of cyanite to muscovite is often pronounced.
Weathering has partially discolored the cyanite a brownish yellow from
free hydrous oxide of iron, also to some extent the lazulite, but the most
noticeable effects in the latter mineral are the dulling of luster and lighten-
ing of color. '
Professor Shepard* remarks that the rock becomes schistose near the
southern extremity of the formation, and contains in addition to the min-
erals mentioned minute crystals of pyrite, occasional drusy cavities nearly
filled with massive crystalline barite enclosing perfectly formed minute
crystals of quartz, and traces of gold. He adds further that the formation
at this point has been worked to some extent for gold, and from its resem-
blance to the diamond gangue (itacolumite) of Brazil it is worthy of careful
examination for the occurrence of diamonds. A partial chemical analysis
of the rock collected on top of the mountain gave SiO2, 69.74 per cent;
A1203, 24.86 per cent; and Fe2O3, 0.53 per cent.
* Op. cit, 1859.
GEOLOGY OF GRAVES MOUNTAIN 209
Microscopically, thin sections of the massive quartzite show a fine
granular mosaic of closely interlocking angular quartz, shreds of muscovite,
and some cyanite in large crystals. Neither biotite nor feldspar was iden-l
tified in any of the thin sections of either phase of the rock or in any of
the hand specimens. Quartz greatly predominates. Rutile is present in
every thin section examined, usually as separate grains and as inclusions
in the quartz and cyanite. Most of the quartz anhedra are approximately
of the same size but frequently occasional larger individuals occur which
show strain shadows and peripheral granulation. The quartz contains
liquid and solid inclusions, dustlike particles of an indeterminate character
and rutile being the commonest of the solid forms. Alteration of the indi-
vidual minerals, including lazulite, as shown under the microscope is described
below separately under each mineral.
MIN ERALOGY.
The mineral association at the Georgia locality is somewhat similar
to that at Clubb and Crowder Mountains, North Carolina. The minerals
include pyrophyllite, lazulite, rutile, cyanite, and hematite, and are de-
scribed below in the order named.
Pyrophyllite. Pyrophyllite, a hydrous aluminum silicate correspond-
ing to the formula H2Al2Si4O12, occurs at Graves Mountain, Georgia, in
stellate or radiate aggregates, a less frequent occurrence of the mineral
than in foliated or compact massive forms. The radiate form of occurrence
has been noted at several localities in the United States,* chief among
which are the Chesterfield district in South Carolina; Graves Mountain,
Lincoln County, Georgia; Cottonstone Mountain, Mecklenburg County,
North Carolina; and the Kellogg lead mine, near Little Rock, Arkansas.
Genthj reports the occurrence of lazulite and cyanite with pyrophyllite
at the South Carolina locality, a similar association to that of Gaston
County, North Carolina, and Lincoln County, Georgia.
Very few good exposures of pyrophyllite were observed on Graves
Mountain. The best and largest one occurs some distance up the north-
west slope on either side of the road which leads on top of the mountain
from the northwest side. Here the mineral is exposed as a solid mass of
several feet in thickness in greatly weathered and etched low cliffs. It
forms fibrous radiate aggregates averaging about a quarter of an inch in
diameter, partially discolored a light dirty brown from infiltrating iron
* Dana, E. S., A System of Mineralogy, 1900, 6th ed., p. 692.
TGenth, F. A., Amer. Journ. Sci., 1854, vol. 18, p. 410.
210 UNIVERSITY or VIRGINIA PUBLIoAT1oNs
oxide. When fresh the folia are soft and flexible, have pronounced greasy
feel and pearly luster, and show basal cleavage. One specimen shows, in
addition to the fine sugary quartz of the enclosing rock, clear and trans-
parent quartz in larger grains, which are regarded as indicative of forma-
tion from solution. Specimens of pyrophyllite in vein quartz collected
from Graves Mountain are on exhibit in the State Museum in Atlanta.
A part of the central portion of a second specimen was occupied by a sponge
of iron oxide, indicating the presence originally of some mineral other than
pyrophyllite removed by weathering and yielding the iron oxide.
In addition to the vein-like occurrence of pyrophyllite, the mineral is
frequently distributed through the quartzite in small particles and large
masses measuring 8 or 10 inches in thickness, and is sometimes associated
more or less closely with cyanite and rutile. Veatch* observed pyrophyllite
in the vein quartz breccia but states that it does not show evidence of
crushing and must therefore have been formed subsequent to the fracturing
of the quartzite.
The exact relations of the pyrophyllite to the surrounding quartzite were
not conclusively established, since contacts were largely obscured, but
the field evidence suggests formation by probable filling of a fracture or
other irregular spacing in the rock. This explanation finds confirmation
in a second occurrence of pyrophyllite recently noted by Veatch in the same
county about seven and one-half miles east of Lincolnton on the Peters-
burg road. Mr. Veatch informs us that both the mineral and enclosing
rock are very similar in texture and appearance to those at Graves Moun-
tain to the west, and that the pyrophyllite fills fractured quartz veins in
the quartzite. Although careful search was made no rutile was found in
the veins at this locality.
In thin sections the microscope resolves the pyrophyllite aggregate
into a series of extremely minute fibers which are mostly radiate in arrange-
ment, sometimes parallel, with all intermediate relations observed. The
mineral is colorless in thin section, has strong birefringence, and contains
some small inclusions of rutile and magnetite or ilmenite. Yellowish-
brown iron oxide has filtered in along and between the boundaries of the
fibers in places, causing discoloration.
An analysis of the pyrophyllite from this locality (column I), compared
with one of the same mineral from the Chesterfield district, South Carolina,
(column II), is given below.
* Personal communication, January, 1912.
GEoLoGY OF GRAVES MOUNTAIN - 211
Analyses of pyrophyllite from Graves Mountain, Lincoln County, Georgia, and Chester-
field district, South Carolina.




I 13 H
SiO2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 64.90 1.082 4 66.01
26.88 0.264 1 28.52
Fe2O3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.18 0.008 0.87
H20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.69 0.317 1.1 5.22
MgO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.17 ' 0.004 0.18
CaO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0:74 0.013 0.23
I 99.57 101.03
Specific gravity. . . . . . . . . . . . . . . . . . . . . . . . . . . 2.659

I corresponds to the formula
O1‘ H2Al2SI4012
I. Pyrophyllite in yellowish stellate or radiate aggregates collected by Thomas L.
Watson from Graves Mountain, Lincoln County, Georgia. J. Wilbur Watson,
analyst.
Ia. Ratios from I.
II. Pyrophyllite in radiated aggregates with lazulite and cyanite from Chesterfield
district, South Carolina. F. A. Genth, Amer. Journ. Sci., 1854, vol. 18,. p.
410. Quoted by Dana, E. S. A System of Mineralogy, 1900, p. 692; and
Hintze, C. Handbuch der Mineralogie, pp. 829, 831.
Lazulite. Lazulite is a rather rare mineral, a phosphate of alumina
containing some magnesia and protoxide of iron, corresponding to the form-
ula (AlOH)2(Mg1Fe) (PO4)2 in which the ratio of Fe :Mg(Ca) varies from
1 : 12 to 2 : 3.* ‘ The known localities in which the mineral occurs in the
United States]L are limited to three in North Carolina, and one each in
South Carolina and Georgia. The North Carolina localities include Clubb
and Crowder mountains in Gaston County, and Sauratown in Stokes
County, the South Carolina locality includes theChesterfield district, and
the Georgia locality is Graves Mountain in Lincoln County. The mode of
occurrence, including kind of rock and mineral associations, is similar for
the localities in Gaston County, North Carolina, and Lincoln Gounty,
Georgia, except that corundum which is unknown in the Georgia locality
is an associate in the North Carolina localities. According to Genth,I the
* Dana, E. S., A System of Mineralogy, 1900, pp. 798-799.
I Mr. Frank L. Hess of the U. S. Geological Survey informs the senior author that
he has received massive specimens of lazulite from California. N 0 published
description of the locality has appeared and, so far as we are aware, nothing is
known of the exact occurrence of the mineral.
I Genth, F. A., Amer. Journ. Sci., 1854, vol. 18, p. 410.
212 UNIVERSITY or VIRGINIA PUBLICATIONS
mineral association in the Chesterfield district of South Carolina is pyro-
phyllite and cyanite.
The mineral has been noted in a variety of occurrences and mineral asso-
ciations, both in the massive and crystallized form, from a somewhat large
number of widely separated foreign localities.* The occurrences include
several localities each in Salzberg and Styria, Austria; several each in
Switzerland and Sweden; at Gulabgarh, India; Tijuco in Minas Geraes,
Brazil; and near the entrance of Churchill River into Husdon Bay, Kee-
watin, Canada. From the published descriptions the occurrence and
mineral association of lazulite at Horrsj6berg in the district of Elfsdalen,
Sweden, bears striking resemblance to the occurrences in North Carolina
and Georgia.
Probably the first occurrence of this rare and interesting mineral in the
United States was noted by Dr. H. S. Hunter]L in 1822, near Crowder’s
Mountain in the southern part of Lincoln (now Gaston) County, North
Carolina. Specimens were forwarded by Hunter to Professor Olmsted
of the University of North Carolina and were noted in the latter’s report
(second part) to the Board of Agriculture. A few years later the mineral
was found in greater abundance near the southern end of Clubb’s Mountain
about thirty miles northeast of Crowder’s Mountain. Hunter reports
the occurrence of lazulite in the latter locality in arenaceous and micaceous
quartzite, occasionally embedded in compact quartz, and in the triangular
cavities of a reddish cyanite. According to this observer the mineral is
massive but imperfect crystallizations may be observed in some specimens.
Later observersi noted the occurrence of the mineral in the Gaston County
localities in pale and dark blue crystals and crystalline masses in quartz-
ite associated with rutile, cyanite, pyrophyllite, corundum, quartz, and
damourite.
The chief interest in lazulite at present is scientific, although apart from
its value as museum specimens, the mineral would probably make an opaque
gem or ornamental stone, as the color which is usually lighter than lapis
lazuli for which lazulite when first found was mistaken, is often equally
as rich.§
At the Georgia locality (Graves Mountain), lazulite occurs in the mas-
sive, fine-grained, sugary quartzite (itacolumite) which, according to Shep-
* Dana, E. S., Op. cit., p. 799.
T Hunter, C. L., Amer. J ourn. Sci., 1853, vol. xv, pp. 376-377.
I Genth, F. A., Proc. Amer. Phil.Soc., 1873, vol. xiii, p. 367. Kunz, G. F., N. C.
Geol. Survey, Bull. 12, 1907, p. 57.
§Kunz, G. F., Op. cit., p. 57.
GEOLOGY or GRAVES MOUNTAIN 213
ard* has a thickness of more than 300 feet, and “presents numerous in-
cluded zones or layers, varying from one to three feet in thickness, in which
is found imbedded, masses and crystals of lazulite.” The observations of
the senior author, which were incomplete from want of time, did not indi-
cate the distribution of lazulite along zones or layers in the quartzite, but
rather as numerous crystals in single individuals and aggregates of very
irregular distribution. The occurrence of the mineral in places sometimes
suggested a tendency to form nests and bunches in the rock.
The lazulite almost invariably occurs as crystals ranging in size up to an
inch and more in length, bounded by crystal faces——combination of prisms
and pyramids, and in cross section from irregular to squarish and triangu-
lar in outline. The crystals are opaque, of deep azure blue color when
fresh but of lighter or paler color after prolonged effects of weathering,
have uneven fracture and indistinct cleavage, but pronounced vitreous
luster. The monoclinic crystals are acute pyramidal in habit, occasionally
flattened from extension of the pyramidal faces, and are frequently twinned.
Professor Shepard]L described and figured five crystals of lazulite from this
locality and remarked that a twin (fig. 5) “is by far the most abundant
form, equalling in frequency all the others combined.”
The lazulite is frequently intimately associated with greenish to color-
less, massive, columnar cyanite partially altered to muscovite, and small
red crystals of rutile. Frequent small crystals of rutile are observed in
the quartzite by aid of the lens. Weathered surfaces offilthe rock are quite
. rough showing characteristic pitting from resistant coarse cyanite and lazu-
lite in relief, with the fine-grained sugary quartz falling out from probable
granulation, forming the depressions. Scales of colorless mica are con-
spicuous in the weathered specimens.
In thin sections under the microscope, the lazulite is usually some shade
of light blue, with pleochroism varying according to depth of color, it being
distinct in the deeper colored sections and weak in the light-colored ones.
It has the pleochroism X colorless or nearly so, Y and Z azure blue. The
absorption is Z = Y > X. The index of refraction is moderate, double
refraction strong; cleavage is indistinct but numerous irregular fractures
occur. The axial angle is large being 2 EI = 111° as determined by von
Lasaulx. The lazulite contains inclusions of rutile and quartz, and occa-
sionally cyanite and muscovite. Alteration has progressed along the
periphery and fractures or cracks, yielding very minute scales and fibers
* Op. cit., 1859.
T Op cit., 1859.
214 UNIVERSITY or VIRGINIA PUBI.IcATIoNs
of a light gray nearly white substance, sometimes stained with iron oxide,
having high refraction and double refraction, and can probably be ‘referred
to hydrargillite as suggested by Rosenbusch.* The common mineral asso-
ciates of the lazulite in thin sections are quartz, cyanite, rutile, and musco-
vite. These may be discerned megascopically in the hand specimens.
.In the following table are given the analysis of the lazulite from Georgia,
and analyses of lazulite from North Carolina, Canada, and Sweden:
Analyses of Lazulite from Graves Mountain, Lincoln County, Georgia, and other localities.




.1 II na , III IV* VT
38.25 40.57 284 1 43.76 42.52 46.39
Al2O3............... 33.92 35.97 353 1.2 31.70 32.86 29.14
FeO . . . . . . . . . . . . . . .. 3.99 4.23 58 8.17 10.55 2.09
MgO . . . . . . . . . . . . . .. 9.08 9.63 241 1.3 10.04 8.58 13.84.
CaO................ 3.12 3.31 59 trace 2.837
H20 . . . . . . . . . . . . . . .. 5.83 6.21 350 1.2 5.59 5.30’ 6.47
6.05 1.07 ~
100. 24 100.00 100. 33 99. 81 100. 76
Specific gravity... 2.958 3.122 . 2.78 3.045


* MnO-—trace.
I Deducted 3 per cent S102.
1 corresponds to the formula '
(F6, Mg, Ca) O.Al2O3.P2O5.H2O
FeO: Mg(Ca) O = 1 :5
MgO:CaO = 1 :3
I. Lazulite collected by Thomas L. Watson from Graves Mountain, Lincoln County,
Georgia. J. Wilbur Watson, analyst.
II. I calculated to SiO;> free basis.
IIa. Ratios from II. ,
III. Lazulite from Gaston County, North Carolina; average of two analyses. Smith
and Brush, Amer. J ourn. Sci., 1853, vol. 16, p. 670.
IV. Lazulite from Horrsjiiberg, Sweden. (Ingelstr6m, 'Journ. pr. Ch., 1855, vol.
64, p. 253). Quoted by Dana, E. S., A System of Mineralogy, 1900, 6th ed.,
p. 799.
V. Lazulite fromnear mouth of Churchill River, Keewatin, Canada. Hoffman, Ch.,
. Geol. Surv. of Canada, 1878-79, p. 2.
Rutile. Knowledge of the occurrence of rutile at Graves Mountain was
early made known by Professor Charles U. Shepardt who was the first to
* Rosenbusch-Iddings, Microscopical Physiography of Rock Making Minerals, 1893,
p. 236.
TShepard, C. U., Op. cit., p. 36.
GEOLOGY or GRAVES MOUNTAIN ' 215
describe and work it. According to Kunz* the rutile from this locality has
realized at least 320,000 for cabinet specimens and has supplied the col-
lections of the world. The rutile was won from the central depression on
top of the ridge and along the northwest slope. The openings are of long
standing and had so greatly caved at the time of the senior author’s visit
in March, 1911, that they were largely obscured. .
N o specimens of coarse rutile were observed by the senior author durin
his visit but it is plentiful in every specimen collected, chiefly as microscopic
inclusions in other minerals and frequently as small crystals and grains visi-
ble to the naked eye. It has been observed megascopically in the quartzite,
and in intimate association with cyanite, lazulite, pyrophyllite, and hema-
tite. As a microscopic accessory rutile in crystals and formless grains of
red and reddish-brown color has been identified as inclusions in the lazulite,'
cyanite, pyrophyllite, hematite, and quartz, and formed along the bound-
aries of these minerals. In each case it shows the usual optical properties.
Veatch]L observed rutile with quartz and iron oxide in veins not exceed-
ing a few inches in width on top of the mountain. The rock fragments
thrown out of the small pits on top of the mountain show fracturing and
brecciation, and formation of the vein rutile was probably subsequent to
the fracturing of the quartzite but a part of it may have existed in the veins
prior to the crushing. '
The coarse rutile crystals from this locality observed in the various
mineral collections in this country are lustrous black to reddish-brown and
red, with brilliant orange red in thin crystals. They vary in size usually
up to 5 inches and occur both as single and twin forms. Kunzl reports
fine single crystals have been found up to four pounds each and with it very
interesting hydrous anthophyllite.
The single crystals are usually prismatic with frequently pyramidal
terminations shown.
Besides the common forms of rutile crystals this locality has furnished
some rather rare and interesting ones, which have been figured and de-
scribed chiefly by German crystallographers,§ especially Rose, Haidinger,
vom Rath, and Miigge. Especially interesting are the beautiful rutile
twins figured and described by Rose and others, composed of as many as
six- and eight-fold twins commonly known as sixlings, and eightlings;
* Kunz, G. F., N. C. Geol. Survey, Bull. 12, 1907, p. 52.
1' Personal communication, January, 1912.
It Personal communication, February 28, 1910.
§ See Dana, E. S., A System of Mineralogy; and Hintze, C., H andbuch der Miner-
alogie for references. '
216 ' ' UNIVERSITY or VIRGINIA PUBLICATIONS
those made up of a less number of parts, such as trillings and fourlings being
not uncommon from the Georgia locality. ,
The three following analyses quoted by Hintzeserve to show the essen-
tial chemical composition of the Graves Mountain rutile.
Analyses of rutile from Graves Mountain, Georgia.

T102 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97.22 97.52 97.64
F8203 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2.62 2.64 2.61
99.84 100.16 100.25
While coarse rutile was not observed at this locality by the senior author,
careful examination of the dumps alongside the numerous openings on the
northwest slope of the mountain from which the mineral was mined, and
the presence of rutile in microscopic proportions in thin rock slices, clearly
' indicate the rutile matrix to be a heavy, dark-colored rock, composed of an
aggregate of long bladed and coarsely columnar crystals of cyanite and
massive granular hematite, with usually some quartz. Frequently the
rock is composed of excessive hematite with less cyanite, and as often cyan-
ite may predominate. In either case the rock presents a more or less porous
texture which perhaps is most pronounced in specimens showing dominant
cyanite. Professor Shepard’s description of the occurrence of rutile in
this rock follows. He says:"‘
The central part of the mountain, to the thickness of 50 feet, is composed of a hema-
titic rock, which includes in some places an abundance of a ferruginous kyanite, much
resembling in appearance the diaspore from the U rals. With the kyanite is found
rutile, often in gigantic crystals (weighing upwards of a pound), and possessed of
much regularity of crystalline form. The prevailing figure is a square prism with
truncated lateral edges, and surmounted at both extremities by an eight-sided pyra-
mid. There is also found a most remarkably perfect twin crystal, in which the
geniculation is six times repeated,-—producing an hexagonal prism, surmounted at
each end by a six-sided pyramid, with a reéntering, six-sided hopper-shaped cavity,
at the tips. These crystals are all more remarkable for their symmetry and polish,
than any I have ever seen. Some are fully equal in lustre to the brilliant crystals of
cassiterite from Cornwall or Bohemia. The most perfect rutiles are generally im-
bedded in the massive kyanite ; and when detached leave behind impressions having
a polish and lustre equal to that of their own planes. A little common quartz is also
mingled with the kyanite and rutile.
Closely associated with kyanite, rutile and quartz, are considerable masses (8 or
10 inches thick) of a mineral known among the miners of Georgia as steatite, but which
is true pyrophyllite,—differing in no respect from that of the Urals, except in the finer
stellulations it presents, and in the slight ferruginous stain it exhibits near their
centres.
* Op. cit., 1859.
GEOLOGY or GRAVES MOUNTAIN ' 217
Cyanite. Cyanite is very generally but irregularly distributed through
both phases of the quartzite composing the mountain, and is intimately
associated with rutile, lazulite, pyrophyllite, coarse crystalline quartz, and
hematite. It is a prominent constituent of the rutile-bearing rock, chiefly
a mixture of cyanite and hematite with quartz; and it is frequently a'con-
spicuous mineral in the lazulite-bearing quartzite (itacolumite), especially
in the lazulite areas. It forms long bladed and coarsely columnar forms
up to several inches in length, is usually colorless though green is not
uncommon. In the weathered portions of the rock cyanite is partially
discolored a yellowish brown from iron stain. Muscovite is a frequent
associate and is derived in part at least from the alteration of cyanite.
In thin sections under the microscope the cyanite is colorless and non-
pleochroic. It usually shows polysynthetic twinning in broad bands, and
good cleavage parallel to the direction of elongation (100) and less often
.and less well developed a second cleavage parallel to 010. Fracture is
common. The cyanite contains inclusions of rutile and quartz, and in
some cases it forms inclosures in the lazulite. The rutile inclusions usually
show perfect crystal boundaries and the mineral is some shade of red in
'color. Rutile as formless grains sometimes occurs along the boundaries of
the cyanite and other minerals. Concerning the coarse rutiles Professor
Shepard* remarks: “the most perfect rutiles are generally imbedded in
the massive kyanite; and when detached leave behind impressions having
a polish and lustre equal to that of their own planes.”
An interesting feature of the cyanite is its alteration to muscoviteI and
iron oxide. The cyanite of the rutile matrix has been designated by Shep-
ardI a ferruginous cyanite. Muscovite in scales is frequently observed on
the cyanite by the naked eye and in such relations as to leave no doubt of
its derivation from the cyanite by alteration. This is entirely confirmed
by the Inicroscope. Thin sections often show the cyanite to have frayed-
out or ragged ends altered to muscovite shreds, and at times the cyanite
substance is clouded by muscovite scales, not infrequently discolored by
reddish brown oxide of iron. Iron oxide has formed along cleavage and
fracture directions and, in case of the rutile matrix, it masks much of the
cyanite substance.
In the table below is given an analysis of the Graves Mountain cyanite
" * Op. cit., 1859.
T Watson, Thomas L. and Watkins, J. H., Association of Rutile and‘Cyanite from
a New Locality. Amer. Journ. Sci., 1911, vol. 32, p. 200.
I Op. cit., 1859.
218 UNIVERSITY OF VIRGINIA PUBLICATIONS
(1), together with analyses of the mineral from North Carolina (II),
Sweden (III), and Canada (IV).
Analyses of Cyanite.


I : Ia II III IV
S102 . . . . . . . . . . . . . . . . . . . . . . . .. 39.14 } 0.652 1 37.60 40.02 36.29
A1203 ...... . .~ . . . . . . . . . . . . . . . . 59.52 0. 584 1 1 60.40 58.46 62.25
1.09 0.007] 1.60 » 2.04 0.55
CaO . . . . . . . . . . . . . . . . . . . . . . . .. 0.18 0.004 I 1.06
MgO . . . . . . . . . . . . . . . . . . . . . . .. 0.40 , 0009 I ' 0.36
’100.33 99.60 '100.52 I 100.51
Specific gravity. . . ._ . . . . . . . . . . 3.282 I

I. Cyanite collected by Thomas L. Watson from Graves Mountain, Lincoln County, _
Georgia. J. Wilbur Watson, analyst.
Ia. Molecular ratios from I. '
II. Cyanite, Lincoln County, North Carolina. (Smith and Brush, Amer. Journ.
Sci., 1853, vol. 16, p. 371.) .
III. Cyanite, Horrsjiiberg, Sweden (Ingelstr6m, J ourn. prakt. Chem., vol. 64, p. 61). '
IV. Cyanite, British Columbia. (Hoffman, Rept. Geol. Surv. Canada, 1878-79', p. 1.)
Hematite; Hematite was observed as an important constituent of the
rock at all the openings from which rutile had been won. Together with
cyanite and less quartz it forms the rutile matrix, which according to Shep-
ard* marks a band 50 feet in thickness. The hematite is massive granular,
steel-gray to red in color, has filled in the spaces between the blades of
cyanite, and presents a somewhat roughened surface. At times it presents
an open or cellular texture due, according to Shepard, to “including the
decomposing ferruginous cyanite, particles of pyrophyllite, and even por-
tions of compact rutile.” The ratio Of hematite‘to cyanite is variable,
sometimes one sometimes the other mineral is in excess. On weathered
surfaces cyanite and -quartz stand out in relief.
Thin sections show an aggregate of cyanite blades and steel-gray hem-
atite, with some quartz and rutile. Hematite fills the cyanite interspaces
and is formed as rims around, and along the cleavage and fracture direc-
tions in, the cyanite. Rutile occurs as inclusions in the principal minerals.
Cyanite is partly altered to muscovite, and in some hand specimens the,
cyanite individuals are more or less curved and bent.
* Op. cit., 1859.
GEOLOGY OF GRAVES MOUNTAIN 219
Mineral Genesis.
Genesis of the minerals of the unusual association noted at Graves
Mountain cannot be considered entirely solved until more detailed work in
the field has been accomplished. The quartzite in which the minerals
occur affords evidence of both anamorphic and katamorphic changes.
Anamorphism is shown chiefly in the production of foliation, the formation
of certain characteristic heavy minerals, and recrystallization. Crushing,
fracturing, and brecciation of the quartzite, and the occurrence of quartz
veins are structures characteristic of the zone of fracture or katamorphism.
No intrusions of igneous rocks of any kind have been observed at Graves
Mountain, although granites and basic igneous types are known at several
localities some miles away. -It is not known whether the igneous rocks are
older or younger than the quartzite composing the mountain. The age
of the rocks has not yet been determined but reasoning from similarity of
lithologic types of widely separated areas it seems not improbable that the
Graves Mountain quartzite will prove to be of Cambrian age. No evi-
dence is available at present for regarding the minerals as having formed
from the effects of intrusions of igneous rocks.
Dr. Genth regarded the minerals of this locality, except rutile and
quartz, as secondary products derived from the alteration of corundum.
He says :*
The same association of cyanite, rutile, pyrophyllite and lazulite in an arenaceous
sandrock is found at Graves Mountain, Lincoln County, Georgia, and although as
far as I am aware, corundum has never been found at this place, there can be very
little doubt that at this locality also all these species except rutile and quartz owe
their existence to the former presence and subsequent alterations of corundum.
Not only has corundum never been found at Graves Mountain but the
authors have discovered no evidence for regarding the minerals as having
been derived from such alteration.
From the evidence already developed in this paper and from the state-
ments which follow below, it seems probable that the minerals at this
locality were not all formed at the same time nor under the same condi-
tions. Pyrophyllite, a hydrous silicate of aluminum, belongs to the kao-
linite group of minerals, the better known members of which are secondary,
the products of hydrous alteration of other species,I chiefly feldspars.
They are produced under the conditions of katamorphism. Stellate struc-
* Genth, F. A., Corundum, Its Alterations, and Associated Minerals. Proc. Amer.
Phil. Soc., 1873, vol. 13, p. 382.
I Clarke, F. W., Bull. 491, U. S. Geol. Survey, 1911, p. 395.
220 UNIVERSITY OF VIRGINIA PUBLICATIONS
ture of the pyrophyllite and lack of evidence indicating the original mineral .
from which it was derived, suggest more than the usual processes of resid-
ual weathering to explain the formation of pyrophyllite at the Georgia
locality. Structure and other conditions of occurrence strongly suggest
formation of pyrophyllite at this locality from solution,‘ as the final stage
in genesis. Likewise the relations of hematite to the associated minerals,
as shown more especially in the study of thin sections, indicate that it was
formed in the zone of katamorphism. On the other hand the cyanite and
in large part the rutile are regarded from microscopic evidence as products
of dynamic regional metamorphism, formed therefore under anamorphic
conditions. The very narrow quartz veins which sometimes carry rutile
and hematite were formed under different conditions, probably as products
of the deep vein zone.
Thus far the rather rare mineral lazulite has been noted chiefly in quartz-
ite of different ages in separate crystals and in pockets and veins. It has
been observed in narrow veins in clay slate near Werfen in Salzberg, in
massive veins in quartzite in the district of Keewatin, Canada, and in
the iron mine at Scania in Sweden. These occurrences clearly indicate
formation of lazulite as solution deposits under katamorphic conditions.
The occurrence of lazulite at Graves Mountain as observed by the authors
was not in veins but as separate and grouped crystals and aggregates dis-
tributed through the rock in intimaterassociation with cyanite and rutile.
The evidence thus far obtained at the Georgia locality is regarded by the
authors as indicating formation of the lazulite under the probable condi-
tions of dynamic regional metamorphism.
LITERATURE .
DANA, E. S. A System of Mineralogy, 1900, 6th ed., pp. 239, 692.
DANA, J. D. Seventh Supplement to Dana’ s Mineralogy. Amer. J ourn. Sci., 1859,
vol. 28, pp. 128-144. For lazulite, Graves Mountain, Ga., see p. 138;
rutile, p. 141.
GENTH, F. A. Contributions to Mineralogy. Amer. Journ. Sci., 1854, vol. 18, p. 410.
Corundum, Its Alterations, and Associated Minerals. Proc. Amer. Phil.
Soc., 1873, vol. 13, pp. 361-406.
Contributions to Mineralogy. Proc. Amer. Phil. Soc., 1882, vol. 20, pp.
381-404.
HAIDINGER, M. W. Die Rutilkrystalle von Graves’ Mount in Georgia, U. S. N. A.
Sitzungsberichte Alc., Wien, 1860, vol. 39, pp. 5-9, 2 figs. of rutile crystals.
HINTZE, C. Handbuch der Mineralogie, pp. 161, 829, 831, 1617-1618, 1622.
HUNTER, C. L. Notices of the Rarer Minerals and New Localities in Western North
Carolina. Amer. Journ. Sci., 1853, vol. 15, pp. 376-377.
GEOI_.OGY OF GRAVES MOUNTAIN 221
_JONES, S. P. Gold Deposits of Georgia. Bull. No. 19, Georgia Geol. Survey, 1909,
pp. 53-62, 248-254.
KUNZ, G. F. Gems and Precious Stones of North America. New York, 1890, pp.
191, 192-193. '
History of the Gems Found in North Carolina. Bull. N o. 12, North Car-
olina Geol. Survey, 1907, pp. 52, 57-58.
LASAULX, A. VON Optisch-mikroskopische Untersuchung der Krystalle des Lazulith
von Graves Mt., Lincoln CO., Georgia, U. S. A. Sitzungsber. d. Niederr-
hein. Ges., Bonn. 1883, p. 274.
MUGGE, O. Bemerkungen iiber die Zwillingsbildung einiger Mineralien. N. J ahrb.
f. Min., 1884, I, pp. 216-234. For rutile at Graves Mountain, Ga., see p.
221 et seq.
Zur Kenntniss der Flachenveranderungen durch Secundétre Zwillingsbild-
ung. N. J ahrb. f. Min., 1886, I. pp. 137-154. For rutile see pp. 147-154.
Mineralogische Notizen. N. Jahrb. f. Min., 1897, II, pp. 67-85. For
rutile see pp. 82-84.
PRATT, J. H. Mineralogical Notes on Cyanite, Zircon, and Anorthite from North
Carolina. Amer. J ourn. Sci., 1898, vol. 5, pp. 126-128. For Graves Moun-
tain, Ga., see p. 127.
RATH, VOM G. Die Krystalle aus Arkansas und Georgia ungehend verglichen.
Verh. N aturhistor. Ver. Rheinl., Bonn. 1877, p. 185; Idem, 1884, p. 297.
Allgemeine Sitzung vom 8 Nov. 1880. N iederrhein. Ges., Bonn, 1880, vol.
37, p. 239.
Mineralogische Mittheilungen, n. F. (Mit taf. I u H). 13. Ein neuer
Beitrag zur Kenntniss der Krystallisation des Cyanit. Groth’s Zeitschr.
f. Krystallographie und Mineralogie, 1881, vol. 5, p. 23.
ROSE, VON G. Ueber eine neue Kreisformige Verwachsung des Rutils. Pogg. Ann.,
1862, vol. 115, pp. 643-649. 9 figs. of rutile crystals.
SHEPARD, CHAS. U. On Lazulite, Pyrophyllite, and Tetradymite in Georgia. Amer.
Journ. Sci., 1859, vol. 27, pp. 36-40.
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