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MINERAL RESOURCES, 1914----PART II.
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feldspar
were shipped for pottery purposes and paid most of the expenses of
mining. Among associated minerals are a few dark red opaque garnet
crystals, a little biotite mica, and black tourmaline.
Beryl
crystals have been found abundantly in some parts of the quarry. These
crystals range from small size up to more than a foot in diameter, and
one block was seen on the dump which weighed about 50 pounds. The
majority of this beryl is opaque or only partly translucent, and is
variously colored bluish green, yellowish green, and yellow. In some of
the large crystals there are translucent and clear portions from which
gems can be cut. In other specimens the gems are obtained from small
crystals which are nearly transparent throughout. At one place several
fractured crystals are exposed in a streak of granular gray quartz
along the southwest wall. These crystals are translucent with a few
transparent parts, and are golden yellow to yellowish green in color.
The
gem beryls are quite clear and brilliant, with a wide range in colors,
from pale to dark golden yellow and almost topaz brown, pale to dark
Dlue and bluish green, and some are yellowish green. Kunz mentions
several that were white or colorless.
The
production of beryl from this mine has been large, and in four years
$17,000 worth of gems are reported to have been sold. Mr. Roebling
still has a few specimens snowing the quality of the gem material
obtained from the mine. This deposit of pegmatite or another in the
same lead has been traced for several hundred yards across the hill to
the southwest of the mine, and at a few small openings made there
showed large pure crystals of orthoclase feldspar. Whether gem beryls
would be found by opening this portion of the deposit can not be
determined without further excavation.
A number of beryl crystals have been found in the feldspar quarry of Joseph Halberg, 2-1/2 miles
S. 25° E., of Middle Haddam. This quarry consists of a cut about 35
feet square and 18 feet deep on the inner side, made in a pegmatite
outcrop forming a small steep hill. Besides feldspar the pegmatite
contains much quartz, a quantity of biotite mica, some muscovite, large
black tourmaline crystals, many beryls, opaque red garnet crystals up
to 3 inches in diameter, and columbite in fractured crystals up to
several pounds in weight. The beryl occurs in crystals ranging from
small ones up to those an inch in diameter and several inches long. In
places they are arranged in radial groups in masses of quartz. Most of
the crystals are opaque pale yellowish and greenish, but a few contain
transparent portions that might yield small gems.
GEORGIA.
Specimens
of cut beryl gems found on the farm of T. J. Allen, about 2 miles east
of Vaughn, Spaulding County, Ga., were kindly loaned by Mr. John L.
Davidson, formerly of Griffin, Ga., now of Chester, S. C. The rough
stones from which these gems were cut were found loose in the surface
soil several years ago. On the same hill with the beryls black
tourmaline, rose quartz, smoky quartz, a few garnets, and mica were
found. Mr. Davidson and Mr. Allen sank a shaft nearly 60 feet deep on
what appeared to be the beryl vein, but no crystals were found. On the
same hill are other deposits of pegmatite and it is possible the
beryls were set free by the weathering
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