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PRECIOUS STONES.
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rocks, principally coarse felspatbic granite, which has all decomposed
even to a greater depth than that at which these crystals occur. Most
of them are obtained by digging where one crystal has been found or
striking and unearthing them with a plow. Altogether several dozen
crystals have been found, weighing from 20 to 300 pounds each, and
future working will doubtless bring many fine ones to light. Some of
these afford larger masses of clear rock crystal than have ever before
been found in the United States, and suggest its use for such objects
of luxury as crystal balls, clock cases, mirrors, etc., which are now
to be seen in the Austrian treasury at Vienna.
From
the vicinity of Fairfax county, Virginia, Mr. James W. Beath obtained
quartz with alternate green and white veinings, the green being
produced by chloritic inclusions. When cut it forms an interesting
ornamental stone, and several hundred dollars' worth of it have been
sold.
Mr. H.L. Hosmer reports that crystals of smoky quartz a foot in length are occasionally found at Sterling, Montana.
Chrysoprase.—Mr.
William Irelan, jr., reports from Tulare county, California, beautiful
semi-transparent chrysoprase of fine color. This has also been found in
Douglas county, Oregon.
Agate.—At
Sioux Falls, Dakota, the company that is cutting and polishing the
agatized wood from Arizona and the quartzite found at Sioux Falls has,
after a great deal of experimenting, perfected the methods of sawing
and polishing hard materials so as greatly to reduce the cost. Among
the objects produced were a round column 11-1/4 inches wide and 21
inches high, cut transversely across the tree, so that the heart was
visible on two sides of it, with the radiations in all directions; and
sections measuring 25, 24, 17-1/2, and 13 inches in diameter,
respectively, so highly polished that when turned with the back to the
light they form a perfect mirror. Ad the specimens were brilliant in
color and rivaled any work ever done in hard materials. The company has
removed from the forest 180 tons of material, and 20 tons of sections
have been ground down to show its characteristic beauties. Perhaps
$100,000 worth is now undergoing the cutting and polishing process.
Pectolite.—A
massive pectolite of unusually dense structure has been announced by
Mr. William P. Blake as occurring in Tehama county, California, in
masses of considerable size and susceptible of a high polish. In a
letter to the writer he gives the following description: "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 punctured
surfaces are irregular, without cleavage, but have a silky luster aud
crypto-crystalline structure, exhibited in extremely fine inseparable
fibers, which are radial, curved, and interlaced, and are perhaps
embedded in a siliceous magma, but the fibers constitute the bulk of
the mass. The color is white, with a delicate shade of sea green, and
trans-0194 Mm------36
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