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MINERAL RESOURCES.
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ex-Governor
Bradford L. Prince, of New Mexico. It is contemplated to work the claim
under the name of the New Mexico Turquoise Company, but since October
6, no developments have been made.
Mr.
M. W. Porterfield, of Silver City, New Mexico, has found traces of
turquoise on the surface half a mile from the Azure mine, in the Burro
mountains, 15 miles south of Silver City, and has made excavations to
the depth of about 18 feet. The turquoise has the characteristic green
color of that in the Burro mountains. Whether any fine material will be
found by further digging is a question.
Two other groups of turquoise mines are described by Mr. William E. Hidden as occurring in New Mexico. (See American
Journal of Science, November, 1893, vol. 46, pp. 400-402, and the
Jewelers' Circular, November 1 and November 8, 1893.) The first group
is 15 miles southeast of the Azure Company's mines, in what is known
as the Cow Spring district. Some prospecting had been done for
turquoise, and 60 miles in a southerly direction the locality showed
evidences of prehistoric workings; the matrix containing the trachyte
is very similar to that in . the Burro mountains. The nearest railroad
station, 22 miles north of this locality, was abandoned because of the
scarcity of the blue—the only valuable—shades of turquoise, the
scarcity of water, and the arid condition of the surroundings.
The
most important locality observed by Mr. Hidden is in Doiia Ana county,
in the Jarilla mountains, l50 miles east of the Burro range The mines
are situated here in an arid and desolate region, Las Cruces being 50
miles west, and El Paso 50 miles south. The turquoise is described as
occurring in trachyte containing minute crystals of quartz implanted in
fine crystals of pyrite, granular jarosite and gypsum coating some of
the same. A shaft 70 feet deep has been sunk on the contact with the
porphyry, and turquoise was traced all the way down. This is the light
green material called " Shoo-ar-me " The writer believes that
the phosphoric acid of the turquoise may have been derived from the
limestone beds, adjacent to the trachyte, that may have covered this
trachyte at no very distant date, and suggests that the oxidation of
the pyrite evidently resulted in the decomposition of the kaolin,
limonite, gypsum, and jarosite, and that this is a produet of a subse
quent kaolin, the kaolin being earlier, and the turquoise a secondary
formation, basing his opinion upon the fact that the majority of
turquoise deposits are semiglobular or reniform in outline, although
compact masses are found wholly occupying small cavities.
The
tendency of the turquoise is said to be toward the blue, more so than
at the two other localities, although green varieties were observed
which were attributed to alteration. The turquoise found at a depth of
25 feet or taken from rock was of a rich blue, but it rapidly faded
after being detached from the matrix and becoming dry. At all three of
the localities described by Mr. Hidden the discoveries were due to the
investigation of old turquoise workings which had been considered
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