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Precious stones.
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753
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color, thus forming a beautiful series of tints of color that have merit for a common gem or
for ornamental stone work. Possibly as fine transparent opalescent
rose quartzes as have ever been found were recently obtained, in pieces
free from all flaws, of a fine rose-red with a beautiful milky
opalescence 4 by 5 inches in size, at Bound mountain, Albany, Maine. A
beautiful opalescent quartz has been found at Daw river, Stokes county,
North Carolina. Rose quartz is found at many localities iu the
granites of Colorado, also in fine specimens at the head of Roaring
fork, from near Clear creek, and on Bear creek. It is mentioned by
Hoffmann, from Tuscarora, Moray, and Carlin, and Silver Peak,
Nevada(a); also by Sweet(b) in crystals from Grand Eapids, Wood county,
Wisconsin.
Prase.—Prase
is found always crystallized at the various limonite deposits on
Staten Island, New York. As specimens the mineral is very good indeed ;
groups of crystals are often 8 or 10 inches across, although the
crystals are rarely over one-half inch long and one-eighth inch in
diameter. The color as a rule is a dark leek green of no gem value.
Prof.
W. P. Blake(c) mentions a greenish-tinged quartz resembling datolite in
color, from the French lode, Eureka district, California.
Hoffmann,
in the " Mineralogy of Nevada," mentions prase in crystals at Eeese
river, San Antonio, and occasionally on the mountain near Silver Peak.
A
translucent leek-green variety(d) of chalcedony and quartz occurs in
the syenitic range of the Lehigh, especially at the allanite locality,
5 miles east of Bethlehem, Pennsylvania. Prase is found at Blue hill,
Delaware couuty, in doubly-terminated crystals, in curious crossings
and rosettes several inches across; also in inferior specimens near
Dismal run, Delaware county. Very fine quartz(e) occurs in its massive
variety at George Van Arsdale's quarry, Bucks county; in Delaware
county at Eadnor ; and in East Bradford township, Chester county.
Quartz inclusions.—The
quartz inclusions as they occur in some varieties are sometimes of
great beauty, and constitute an important part of the American gem
minerals. As some of these are quite rare and little known among
collectors, mention of a few of the leading American localities may not
come amiss.(f)
Two
of the finest known specimens of rutilated quartz are of American
origin; they are massive smoky quartz, evidently parts of one crystal.
One of them was originally in the possession of the late Dr. Chilton(g)
as early as 1847, and is now in the Vaux cabinet at the Philadelphia
Academy of Sciences. It is about 7 by 3-1/2 inches, and is
a "Mineralogy of Nevada." b Sweet's "Minerals of Wisconsin." c" Catalogue of Minerals of California," 1866, page 20. d Preliminary report on the Mineralogy of Pennsylvania, page 59. e Preliminary report on the Mineralogy of Pennsylvania, page 58. f See also paragraphs on rutile, amethyst, and garnet.
g "Proceedings American Association for the Advancement of Science," 1849. 2 M R-------48
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