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PRECIOUS STONES.
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GERMANY.
A
large block of golden yellow amber, about 5 incbes long, 4 inches wide,
and 3 inches high, weighing 33 ounces, is reported to have been found
on the beach at Thiessow, Pomerania.° It is said to be free from cracks
or flaws.
AMETHYST.
There
was a small production of amethyst in 1907 from scattered localities.
The largest output came from Nelson County, Va., with smaller
quantities from Amherst County in the same State, Iredell and Macon
counties, N. C, Rabun County, Ga., Fremont County, Colo., and Maine.
In
Macon County, N. C, amethyst has been found at various places in the
region of Tessentee Creek, near Scaly Mountain, and to the south of
Highlands. In Rabun County, Ga., a few miles to the south of the
last-named localities, amethyst has been found at several places within
2 or 3 miles of Clayton and from 12 to 15 miles to the east. The
amethyst of this region occurs in veins cutting granite gneiss and mica
gneiss. The veins in which the amethyst occurs are generally
irregularly filled, well-defined fissures cutting the inclosing rocks
at variable angles, though generally with a high dip. Some of these
veins have been traced several hundred feet. Deep-colored amethyst
crystals are found in pockets in these veins, often associated with
pale amethystine and colorless quartz crystals. The spaces between the
crystals are commonly filled with red clay or other earthy material.
The pockets range from a fraction of an inch to 15 or 18 inches in
thickness, and may extend several feet along the vein. The crystals
range in size from a small fraction of an inch to 3 and 4 inches
across. In some of the crystals the purple color of amethyst is
entirely lacking or present only in pale shades. In others the rich
purple of Siberian amethyst is present. The color is generally most
intense near the points of the crystals and often occurs in planes
parallel to the crystal faces. This renders' only portions of the
crystals suitable for cutting, although much amethyst and quartz
suitable for specimens only is obtained.
The
production of amethyst from Colorado was reported from a new deposit
discovered by Mr. J. D. Endicott, of Canon City. This deposit is near
Parkdale, about 13 miles west of Canon City. Mr. Endicott describes the
vein as 30 inches wide, striking northwest, with a nearly vertical dip,
through decomposed granite. The crystals of amethyst and amethystine
quartz range in size up to 2 inches thick and 3 inches long.
AZURMALACHITE.
The name azurmalachite has been applied by Dr. George F. Kunz to the gems cut from blue azurite combined with green malachite.6 This
form of gem is found in the copper mines of Bisbee and other districts
in Arizona. The combination of minerals occurs in a variety of
different forms, as concentric layers in stalactites, and as globular
and botryoidal masses, etc. Various effects result from cutting in
different directions through the masses, and attractive
" Manuf. Jeweler, April 2,1908. t Eng. and Min. Jour., August 17,1907.
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