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GEMS AND PRECIOUS STONES. 1057
The
greater part of the output of variscite in 1912 came from Utah, where
three mines were operated. Mr. Maguire reports extensive development
at his mine, with the discovery of some fine material. Unfortunately
the claims of Bird & Edison, near Lucin, have fallen under
litigation with the Southern Pacific Co., so that none of the finely
marked "turtle-back" and brecciated variscite from this locality could
be placed on the market. Only one producer from near Coaldale reported
from Nevada in 1912.
Variscite
is a hydrous aluminum phosphate with bright green color. It has a
hardness of only four, and is therefore not suited to rough wear. In
some occurrences it is associated with allied phosphate minerals, among
which is wardite. Other associated minerals and rocks, such as quartz,
chalcedony, chert, jasper and black "jas-peroid," limonite, hematite,
slate, and rhyolite, often form strong contrasts in color and pattern
with the variscite, yielding unique matrix gems. The variations from
light to dark emerald-green in variscite itself, with its unusual
markings due to texture, lend further contrast to these gems.
Innumerable effects can thus be secured in cutting variscite and its
matrix to meet the fancy of the various purchasers. The attractiveness
o"f variscite gems, along with the reasonable price for which they can
be sold, should guarantee their continued use in certain lines of
jewelry, especially in the western tourist trade. Select gems have
sufficient beauty to make them high priced. Variscite is especially
adapted to what has been called barbaric jewelry and is beautifully
"set off" in rich colored filigree gold mounting.
GREEN MICA SCHIST.
T.
Nelson Dale ' has described an occurrence of green mica schist in
Shrewsbury, Vt., which promises to have considerable use as an
ornamental stone. The following notes have been abstracted from his
description of this rock: The occurrence is in a small saddle on the
north side of Hound Hill, on the west flank of the Green Mountain
Range, 3-3/4 miles southeast of Rutland station. It was discovered and
is being jprospected by Edward H. Foley, of Rutland. The schist belt is
about 100 feet thick and has a strike of N. 15°-30° W., with a high
east dip. It consists largely of chrome mica (fuch-site), with some
chlorite, quartz, tourmaline, and a little magnetite. The rough rock
has a bright verdigris-green to faintly greenish-gray color. Its luster
ranges from glistening to waxy and its texture is foliaceous and
plicated. The polished stone has a brilliant dark emerald-green color
varied with fine wavy streaks of lighter green. The stone saws and
polishes well and will be suitable for internal decorations if obtained
in masses of sufficient size and soundness. A block measuring probably
18 by 12 by 8 inches presented to the United States National Museum was
firm and solid through the whole mass. A cube measuring possibly 3-1/2
inches square and two rectangular slabs—one about 7 by 12 inches square
and the other smaller—were cut from one end and side of the block. The
polished face of the cube is rich dark-green of nearly even color. The
slabs show both plicated banded light and dark-green layers and large
areas of a nearly even green color.
I The commercial marbles of western Vermont: Bull. U. S. Geol. Survey No. 521,1912, pp. 50-51.
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