Kyanite, Sillimanite, and Andalusite Deposits of the Southeastern ...

KYANITE DEPOSITS 53
significance. The topaz may be of detrital origin or
may have formed during metamorphism through
introduction of small amounts of fluorine into
alumina-rich rocks.
Taber (1913, p. 27) also concluded that the kyanite-bearing
rocks had been formed by the regional
metamorphism of aluminous sedimentary rocks, but
he thought that "contact action" of granitic intrusions
may have had a part in the metamorphism.
His geologic map (1913, pi. 1) shows a large area
of granitic rocks whose western border lies about
7 miles east of Willis Mountain. We conclude,
however, that the origin of the kyanite quartzite
cannot be closely related to the influence of granitic
intrusions. The only intrusive rocks of this nature
in the vicinity of the kyanite quartzite deposits are
the pegmatites and a few small bodies of biotitequartz
syenite and aplite; there is no relation between
the distribution of these igneous bodies and
the kyanite quartzite.
The weight of the evidence, therefore, is strongly
in favor of origin of the kyanite-bearing rocks by
the regional metamorphism of alumina-rich sedimentary
rocks. Some mobilization of the sedimentary
aluminum did take place during metamorphism,
possibly through hydrothermal action, but it was
probably limited to transfer of aluminum over short
distances to form aggregates of massive kyanite in
the kyanite quartzite and small amounts of kyanite
in some quartz veins in kyanite quartzite.
OTHER MINERAL DEPOSITS
Other mineral deposits within the mapped area
include ferruginous quartzite, pegmatite, and a
small pyrrhotite-bearing deposit that has been
prospected for copper. Gold deposits were mined at
one time in a belt extending north from the north
end of the kyanite district; slate has been quarried
in this same belt at Arvonia for more than 100 years.
IRON
Many of the ferruginous quartzite bodies have
been prospected by trenches and shallow pits. The
Ayre tract, about 3^ miles east of Dillwyn and
just south of Virginia Highway 650 near its junction
with Virginia Highway 668, is a typical deposit
(pi. 2). Variable amounts of magnetite and specular
hematite occur here in layers of fine-grained quartzite
having maximum widths of about 20 feet; massive
manganiferous garnet partly altered to wad is
present in places. One of the shafts here was between
40 and 50 feet deep, according to Taber (1913,
p. 20). The other principal prospects in iron and
manganese-bearing quartzite in the region are along
Virginia Highway 628 about half a mile south of
Buffalo Creek, along U.S. Highway 60 about 0.4
of a mile east of the junction with Virginia Highway
632, in a curved belt that extends for a distance
of about 2 miles east from a point on Virginia
Highway 633 about 0.7 of a mile northwest of
Willis River, and north of Virginia Highway 635
about 3 miles west of Curdsville. Taber (1913, p.
19-22) describes several prospects to the north of
the mapped area. Prospecting of the iron deposits
was probably done when gold mining was most active
in the region, about 1829 to 1861. It is doubtful
that any of the ore was shipped to iron furnaces;
apparently there were no furnaces in the vicinity.
Iron was smelted at several furnaces during the
middle of the past century near James River, about
30 miles to the west (Espenshade, 1954).
PEGMATITE
The numerous pegmatite bodies in the region are
small and have attracted very little prospecting.
A pegmatite in kyanite-garnet gneiss on the saddle
between Willis and Round Mountains was prospected
many years ago by a shaft, 40 to 50 feet deep.
Quartz-feldspar-muscovite pegmatite is exposed in
the lower half of the shaft; most of the mica books
are less than 1 inch in size, though some are as
large as 6 inches. Pegmatite and rock containing
considerable amphibole, pale-pink garnet, and a little
pyrrhotite are found on the dump of this
prospect. Pegmatite prospects outside the mapped
area in Buckingham, Prince Edward, and Charlotte
Counties are described by Jahns and Griffitts (Griffitts
and others, 1953, p. 182-183).
COPPER
A copper prospect at the south end of Round
Mountain has been described by Taber (1913, p.
28, 113-114). Two shafts were sunk here about
1870; they are caved now, and the material on the
dumps gives the only indication of the character of
the deposit. Pyrite and pyrrhotite occur with abundant
amphibole, garnet, plagioclase (An30), and
pale chlorite; a little scapolite is also present.
GOLD
The gold mines and prospects in this region are
outside the mapped area in northern Buckingham
County, and north of James River in Goochland and
Fluvanna Counties. They have been fully described
by Taber (1913). The Morrow, or Booker, gold
mine lies a few miles west of Willis Mountain (pi.
2). Gold mining was most active from about 1829
to 1861. During this period, gold was mined from