|
704 MINERAL RESOURCES, 1913—PART II.
|
||
|
|
||
|
a
hard dense texture necessary for good gems. Brown stains of limo-nite
coat the faces of some of the veinlets and have permeated cracks and seams in them. Such material furnishes attractive matrix gems with varied markings.
A
little turquoise has been found in a prospect at the Maltby
silver-copper mine, about 1 mile south of west of the Texas Turquoise
Co.'s mine. Hardened black siliceous slate is the principal rock at the
Maltby mine, but the turquoise occurs in a small dike or sill of white
partly altered porphyry a few feet thick, which is inclosed in the
slate. A few pieces of greenish-blue turquoise were seen. These were
associated with brecciated porphyry rather heavily stained with
limonite. The only work done for turquoise at this locality consisted
of a small prospect pit 2 feet deep, and, until further work has been
done, the discovery must be considered merely an indication of possible
gem material.
MISCELLANEOUS.
ASTERIA QUARTZ.
Asteria
quartz of exceptionally good quality has been applied to use in jewelry
by Bell & Birknir, of New York. The source of the rough mineral has
not been revealed. The gems are cut round cabochon and are sold as
asteria or star stone. They show a fine bright 6-ray star in reflected
light on a nearly colorless highly translucent background. The cut
stones are very pretty and may be mounted simply or in a girdle of
small diamonds.
HELIODOR.
A
species of beryl has been introduced to the gem world under the name of
"heliodor." ' This material has been very scarce so far and most of it
is in the possession of the Emperor of Germany. It comes from Rossing,
German Africa. Heliodor differs from most beryl in containing a small
percentage of uranium oxide and in being weekly radioactive. The color
by day is golden yellow and by artificial light a delicate bluish
green.
HET AEROLITE.
A
specimen of hetaerolite from Leadville, Colo., was sent in by Mr. W. C.
Hart, of Manitou Springs. This mineral, containing zinc and manganese
oxides, occurs m botryoidal and mammdlary deposits with radiated
columnar structure. According to Dana, it has s hardness of 5 and a
specific gravity of 4.93. The specimen sent by Mr. Hart was cut
cabochon. It is a brilliant black and in certain fights the radiated
structure can be seen.
ICELAND SPAR.
Prof.
J. P. Rowe, of the University of Montana, at Missoula, reports the
occurrence of crystallized calcite, of sufficient transparency to be
classed as "Iceland spar," in Sweet Grass County, Mont,
1 Houdelet, A., Deutsche Goidschmiede Zeitung, abstracted to JeweJers' Circular-WeeiJj-, Apr. 22,Mi. Bauser, Otto, and Herzield, H., Chem.-Zeitung, June 2,1914..
|
||
|
|
||