the west, and several smaller prospect pits scattered over die mountain side.
Other
prospects were made in the gulch north of the camp and on the hills
south of the workings described above. The small developments at these
places indicate that no finds of importance were made.
The
rock exposed in the turquoise-bearing area is a decomposed porphyry of
granitic or quartz monzonitic nature. In some of die less decomposed
phases both pink orthoclase or microcline and white plagioclase can be
distinguished in hand specimens along with quartz and biotite. In some
of the more altered phases there are
rains
of quartz scattered through chalky white masses of scricite, kaolin, or
other alteration products of the original rock. Fracturing and jointing
of the rock have been extensive, doubtless rendering more easy the
decomposition and the spreading of the alteration products. In places
brown and yellowish stains of limonite and jarosite are abundant. The
decomposed rock along some of the fracture zones has been hardened by
limonite acting as binding material or cement. Secondary quartz is
scattered through the rocfc in veinlets and small irregular, masses and
in places scricite has developed plentifully. Clay gouge seams and
veinlets have formed in many of the joints and fractures.
The
occurrence of the turquoise in the different workings is very similar.
A large proportion of it occurs in nugget or nodular form in fractured
portions of the rock, and some occurs in seams and veinlets. In many
places several nodules are grouped together. The nodular turquoise is
embedded in the white claylike masses of the gouge veins or in similar
material in badly altered parts of the rock along fracture zones. The
turquoise nodules removed from this, matrix are coated with white
chalklike shells, which have to he chipped or ground off before the
quality of the gem can be determined. Sencite is an important
constituent of much of the white claylike gouge deposits. In places the
clayhke matrix and associated turquoise have been cemented into hard
masses by limonite. Quartz, in rough crystals, is occasionally
associated with turquoise in some of the veinlets. A quantity of soft
nodular, pale-blue to bluish-green turquoise or semiturquoise, was
found in several of the prospects, especially on the steep spur east
of the main working on die side of Crescent Peak. Limonite stains were
abundant in the surface rock on this spur and indications seemed
favorable for the opening of a good deposit of turquoise. The prospect
shaft at this place faded to locate any good gem material, however. The
nodules of turquoise range in size up to more than an inch across and
generally yield pure turquoise and but little matrix. The better turqi
ranges from light to medium dark pure blue of a shade sometimes called
"baby blue." The texture is dense and the mineral over 6' in hardness.
Owing to the occurrence of most of the turquoise in nodular masse* embedded
in claylike matrix, it was difficult to save all the gem material in
mining and a quantity of good turquoise passed to uie dumps. Some of
these dumps might be profitably worked yet, though their surfaces have
been picked over many times by visitors to the mine. Evidently
turquoise was rather plentiful in the larger workings, as so much was
allowed to go over the dumps and it was still found profitable to carry
on extensive operations.
