ransome.] DEPOSITS OF RED MOUNTAIN REGION. 249 
Magnet mine. — This, an old location, is situated on the east side of 
Mineral Creek, near Burro Bridge. It produced a little rich silver ore 
in the early eighties, but owes its interest at preseni to the occurrence 
of a telluride of silver, probably hessite. 
The workings comprise a tunnel about 540 feet in length and a few 
superficial openings. The lode strikes N. 85° W. and dips from 60° 
to 80° to the south. It is a compact stringer lode, in places 2 feel 
wide, which contains considerable mineralized and altered andesitic 
breccia, which forms the country rock. The stringers are filled with 
quartz, "frozen" to the walls and containing bunches of ore. A 
radial structure of the quartz is common and vugs are numerous. 
The ore, consisting of argentiferous galena, a silver telluride (hess- 
ite?), a little free gold, sphalerite, chalcopyrite, and pyrite, occurs 
partly in the quartz and partly replacing the included fragments of 
breccia. The richest ore, containing the hessite, is usually associated 
with the radial quartz and often occurs in the interstices between the 
outer ends of the crystals. The ore is unevenly distributed through 
the lode and has been found only in small bunches. 
Brobdignag claim. — This abandoned prospeel is of Lnteresl as the 
locality whence some zinkenite was formerly obtained, which was 
described and analyzed by Dr. Eillebrand. 1 No ore was visible in 
L900. The country rock was apparently originally an andesite, but 
is altered to a white aggregate consist ing chiefly of quartz and barite. 
Zunimine. — This mine, well known in mineralogical literature as 
the source of guitermanite and zunyite, is situated near the summit 
of Anvil Mountain, at an elevation of aboul L2,000 feet. The ore 
body was worked from the surface by an open cut and a shaft and 
by two tunnels. The upper tunnel branches, the two breasts being 
150 and 1 so feet in from the surface. A second tunnel, 200 feel below 
the upper one, is 540 feet in length. There is no connection between 
t hese 1 wo 1 unnels. 
The surface ore of the Zuni, discovered in L881, was chiefly massive 
sulphate of lead (anglesite) containing abundant small tetrahedral 
crystals of unaltered zunyite. This soon changed to unoxidized 
guitermanite in characteristic association with zunyite. This was the 
chief ore of the upper tunnel, and occurred in a mass about GO feet 
long and L5 feet wide. Below the tunnel level this bismuthiferous 
Lead ore decreased in width to about •'» feet and changed gradually to 
a copper ore, consisting chiefly of enargite, with pyrite, kaolin, and 
a little barite. The enargite carried about 216 ounces of silver and 
40 per cent of copper. In the lower tunnel the ore body, about 40 
feet long and 1_ feet wide, is a soft mass of kaolin and embedded 
pyrite, with nests of enargite. The pyrite occurs chiefly in octa- 
hedra and is said to carry a very little gold. The ore at this depth con- 
tains many fragments of the immediate country rock, a much altered 
1 Bull. U. S. Geol. Survey No. 20, p. 93. 
