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GEMS AND PRECIOUS STONES.
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beryl
crystals range from less than an inch to 6 inches in diameter. Crystals
of less than 1-1/2 inches diameter are most plentiful. They are
yellowish to aquamarine colored, mostly opaque, with translucent and
small transparent portions. Some of the crystals are penetrated by
crystals of black tourmaline. Small pockets were observed with
pinkish-violet colored lepidolite and variegated tourmaline. The
tourmaline occurs in rough triangular-shaped crystals up to an inch in
diameter. Some of them have rose-pink exteriors and dull greenish to
black cores. Others are solid pink. No transparent tourmalines were
observed, but the presence of cavities indicates a possibility of
their being found.
MAINE.
At
the Mount Mica tourmaline mine, near Paris, Me., work was carried on
for nearly 4 months, but Mr. Loren Merrill, the operator, reports that
only one small pocket was found, yielding a few green tourmaline
crystals. Other products of the quarry are feldspar and a little mica.
Work at this locality is becoming more difficult, since there is 25 to
30 feet of overburden to be removed before the gem-bearing portion of
the ledge can be quarried, and unless underground mining is adopted it
is doubtful whether the deposit can be worked much farther.
On
Mount Apatite, near Auburn, Me., a number of achroite, or nearly
colorless tourmaline crystals, were obtained from the quarry of P. P.
Pulsifer during operations for feldspar.
MASSACHUSETTS.
Colored
tourmaline crystals have been found at several localities in the region
of Goshen and Chesterfield, Hampshire County, Mass. Some of these
localities have been known for many years. An early description of two
of the localities was given by George Gibbs1 in which the
minerals and their distinctive characters are discussed. The two
localities are probably those called the Clark ledge and the Barrus
property below. Shepard 2 speaks of this region as being
rich in variegated tourmalines, among which deep indigo-blue crystals
were abundant. Other colors, green and rose-red, are also mentioned,
and spodumene is reported from the same region. Emerson 3-
quotes Alvan Barrus as stating that tests were made by chemists with
some of the spodumene with a view t-o using it as a source of lithia. A
number of the spodumene deposits have been located on the geologic
atlas of the region by Emerson 4 and colored tourmalines
have been found at some of them. So far as known no clear tourmalines
suitable for gems have been found in this region, but the deposits are
of interest because of mineral associations and the possibility of gem
material being found in the future.
A
brief visit was made by the writer to the region in October, 1914, and
three deposits were examined, one on the George L. Barrus place, 2 j
miles northwest of Goshen, another on the summit of a hill 2 miles
north of West Chesterfield, and the third, known as the Clark ledge,
1 Gibbs on tourmaline, etc.: Am. Jour. Sci., 1st ser., vol. 1, pp. 346-351,1818.
* Shepard, C. U^ Treatise on mineralogy, 3d ed., p. 220,1852.
» Emerson, B. K., Geology of Hampshire County, Mass.: IT. S. Geol. Survey Mon. 19, pp. 760-761,1898.
* Emerson, B. K., U. S. Geol. Survey Geol. Atlas, Holyoke folio (No. 50), 1898.
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