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178 GEMS AND PRECIOUS STONES IN THE
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phia,
Pa., in reddish-brown crystals ; and at the lead mine in Canton, Ga.
At the Parker Mine, Cherokee County, N. C, it occurs in large, coarse,
single crystals and twins; also along Persimmon, Hanging Dog, and Bear
Creeks, Madison County, and Tusqui-tee Creek, Clay County. In the
last-mentioned places staurolite is found in argillaceous and talcose
slates. Some staurolite macles similar to a chiastolite, from
Charlestown, N. H., are described by Dr. Charles T. Jackson. These pass
by insensible shades or gradations into andalusite macles.
Isopyre
is found in small veins from 1 to 3- inches in width in the magnetic
iron at Dickinson Mine in Ferremonte, three miles from Dover, N. J. In
color it very nearly resembles the darker green jasper, or, in other
words, bloodstone without the red spots. It is used as a gem in the
cabinets of collectors. Its hardness is 6-o to 6.5.
Pectolite
was found in quantity among the Esquimau implements collected by the
United States Signal Service at Point Barrow, Alaska, and examined by
Prof. Frank W. Clarke ;' it was at first supposed to be jade, but on
examination proved to be a new and interesting variety of compact
pectolite, in two varieties, one pale apple-green, the other dark
green. The specific gravity of the pale-green variety was 2.873, that
of the dark-green 3.092. This forms an interesting and unexpected
addition to the list of gem stones. During 1887 a massive white
pectolite of unusually dense structure, and susceptible of a high
polish, was announced by William P. Blake as occurring in Tehama
County, Cal., in masses of considerable size. In a letter to the writer
he gives the following description of it: "It occurs in a vein, and is
broken out in rough tabular masses, from 2 to 3 or more inches in
thickness, but it is reported that much larger masses can be obtained.
It is exceedingly tough and hard to break. The fractured surfaces are
irregular, without cleavage, but have a silky lustre, and a
crypto-crystalline structure is exhibited in extremely fine inseparable
fibres, which are radial, curved, and interlaced, and are, perhaps,
imbedded in a silicious magma, but the fibres constitute the bulk of
the mass. Color, white, with a delicate shade of sea-green;
translucent. Exposed or weathered portions lose their porcelain-
1 Am. J. Sci., III., Vol. 28, p. 21, July, 1884.
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