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MINERAL RESOURCES.
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of turquoise than that now found. It is therefore thought probable that the same material will be found again.
The Aztec Turquoise Company ships for cutting only the best
{
pure blue turquoise
and high-grade matrix. Large quantities of low-grade, soft, and
offcolor rough and matrix material is thrown away or buried. The gems
are cut at the company's shop in New York and the pure stones are
guaranteed. They are marked on the back with an AZT monogram occupying
the space of one letter. The best turquoise comes from the Monte Cristo
claim. It has a rich deep blue color and takes a brilliant polish. The
matrix stones show pleasing contrasts between the dark blue of the
turquoise and the dark-brown limonite stains, with sometimes gray
quartz or rock fragments.
The
portion of the William Tell claim worked by the Arizona Turquoise
Company is directly below and adjoins on the south the Monte Cristo
claim of the Aztec Turquoise Company. The deposit is on the steep,
cliff-like northeast slope of Ithaca Peak, down which the waste rock
from the workings slide several hundred feet. The operations consist of
a cut in the mountain side with a working face nearly 50 feet high.
This face is carried back by steps or benches 12 to 15 feet high. Deep
holes are drilled and the rock of the successive benches pushed out on
to the floor of the cut by blasts. In this way masses weighing several
hundred tons are loosened and broken so that they can be sledged and
the turquoise picked out. Where patches of fine blue turquoise occur
they are carefully chipped out with gads and chisels. The turquoise is
closely sorted, only the better grades being shipped. The greenish,
pale blue, and soft turquoise is discarded and destroyed. Some very
fine pure blue turquoise of deep color is obtained, though the
principal yield is in matrix gem material. Guy Atlee, superintendent,
states that occasionally lumps of over a pound in weight of nearly
pure turquoise are obtained. The lumps are generally of matrix and come
from enlarged portions of the turquoise seams. The latter occur
plentifully in parts though without definite position through the
rock. In the workings no attempt is made to follow particular seams
through any distance, but the rock is quarried as a whole, and the
turquoise seams and patches are picked out of the blocks. The method of
the occurrence of the turquoise in decomposed, silicified quartz
porphyry is the same as in the Aztec Company's mine directly above. The
gem material is all shipped and cut at the company's plants in New York
and Denver.
'
The deposit of turquoise worked by the Los Angeles Gem Company, a few
hundred feet northwest of that of the Arizona Turquoise Company, is
also located on the very steep northeast slope of Ithaca Peak, above a
rocky cliff. The mining, which is under the supervision of E. E. Peck,
president of the company, is open-cut work. Large masses of rock are
broken down by blasting, and the turquoise is removed by carefully
breaking the blocks. The turquoise occurs in seams cutting decomposed,
silicified quartz porplvyry in various directions. The principal yield
is in matrix turquoise, though some pure turquoise also is obtained.
The gems are shipped to Los Angeles where they are cut in the company's
shop. An odd stone was recently cut by this firm showing a blue letter
Y of turquoise in a gray matrix. This stone was sent to a student at
Yale University. The cutting so
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