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1060
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MINERAL RESOURCES.
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and
yellowish-red spots, patches, and streaks occur. Some of the plasma has
a uniform color and texture over considerable areas, and some contains
a few patches and streaks of chalcedony and finely crystallized quartz.
A few of the red spots are rounded like drops of blood, but most of the
red is in large or small irregular patches and streaks. The different
patterns formed in the latter case furnish pretty gem material, but the
most valued specimens are those in which the red spots are nearly
uniform in size and distribution through the green. Cut gems of this
bloodstone have been well received in the Southwest and some of them
have brought good prices.
LAZULITE.
CALIFORNIA.
The
writer is indebted to Prof. G. Montague Butler, of the Colorado School
of Mines, for two gems cut from lazulite matrix from California. The
rough material was obtained from Breyfogle Canyon, in Death Valley, by
W. B. Patrick, a former student of Prof. Butler's. The lazulite occurs
in a vein cutting schist. The vein varies from 1 inch to 5 feet in
thickness and can be traced several miles. The lazulite is confined to
a comparatively few patches in the vein. Pure blue gems can be cut from
some of the lazulite, but Prof. Butler states that they are not as
pretty or attractive as those containing matrix. The matrix is chiefly
white quartz with occasional brownish patches and seams. In the
specimens examined the lazulite varies from pale azure blue to fairly
deep azure blue. In one specimen it occurs in both small crystals and
crystal aggregates through the white quartz. In the other specimen
there is a large crystal or crystal aggregate with less quartz. These
gems are unusual and pretty and are said to be very attractive mounted
in silver.
OPAL.
NEVADA.
Further
information regarding the" opal deposits in Humboldt County, Nev.,
mentioned in this report for 1909, has been given by Mr. Ivan Dow, of
Nevada City, Cal. The deposits are on the Miller & Lux ranch,
managed by H. E. Rinehart, about 20 miles south of the Oregon State
line and 40 miles east of the California State fine. Ivan Dow and
George D. Matthewson, of Delta, Utah, own an interest in the opal
deposits and have been encouraged by finding some fine gem material.
Prospecting will be continued during 1912. The precious opal occurs in
part as petrifactions of wood and limbs of trees. In such specimens the
texture of the wood has not been preserved, but the outline remains
with the bark of branches of a slightly different color from the
interior. The opal has been declared of fine quality by dealers. Gems
of excellent quality obtained from this locality have been seen by the
writer.
MEXICO.
A
description of a Mexican opal mine was given by T. M. M. MacFarlane in
a paper read before the Instituto mexicano de minas y metalurgia,
August 7, 1911, of which the following is an abstract:'
1 Taken from abstract in Eng. and Mln. Jour., Oct. 28,1911, p. 842.
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