186 ECONOMIC GEOLOGY OF SILVERTON QUADRANGLE. Tbull.182. 
lower adit tunnel, and an unknown extent of drifts. The mine never 
proved successful, and has been- idle for ten or fifteen years. No 
examination of the underground workings was possible in 1899. 
The Red Cloud lode is a very strong one. It passes through tiie 
saddle just east of Tuttle Mountain, where its individuality is some- 
what obscured by a multitude of intersecting veins. It appears, how- 
ever, to continue along the southeast slope of Tuttle Mountain and 
to form one member of the remarkable plexus of veins about Lake 
Como. Toward the northeast it passes through the Ben Butler claim 
and over the dividing ridge between the Animas River and Hensoii 
Creek drainage. At the Red Cloud mine the lode is split into several 
members, of which the three most prominent are indicated on the 
map. The mine is located on the western or main fissure. 
Inspection of the dumps shows that much of the ore originally filled 
a brecciated zone in rhyolite. The ore contains galena, often dissemi- 
nated in minute particles through the quartz, sphalerite, chalcopy- 
rite, and pyrite, in a quartz and rhodonite gangue. Some of the pyrite 
has the radial structure usually taken as indicative of marcasite. 
(See p. 77; also PL XI C.) Ruby silver (proustite) is also reported. 
The crude ore is said to have contained about $40 and the concen- 
trates about $15 per ton. The process of ore deposition was attended 
by much alteration, impregnation, and possibly some replacement of 
the country rock. Subsequently the ore was brecciated by renewed 
movement along the fissure and recemented by quartz carrying small 
amounts of sphalerite and galena. 
Ben Butler mine. — This is a prospect on the same lode as the Red 
Cloud. The lode dips southeast about 75°. It is less evidently 
brecciated than in the Red Cloud. The country rock is andesite. 
The ore shows much sphalerite, with galena, pyrite, and ruby silver 
(proustite), in a quartz gangue. The different ore minerals are not 
uniformly distributed through the lode, but are more or less concen- 
trated into zones or bands. The best ore is the very finely crystallized 
galena and ruby silver in a quartz gangue. This galena, minutely 
disseminated through the quartz, is called "brittle silver" by the 
miners, but chemical examination shows that this name is erroneously 
applied. These two minerals are practically confined to two streaks 
4 to 8 inches wide. The lode is a large one, and the walls are not 
exposed in the workings. The latter are 100 feet in depth and opened 
through an inclined shaft. The shipping ore is said to run about 40 
ounces of silver, 40 per cent of lead, and a little gold, which some- 
times amounts to 4 ounces per ton. Work on this property was in 
progress in a small way in 1899 and 1900, and a tunnel was being run 
to cut the lode at greater depth. 
Uncomjxihgre Chief claim. — This prospect, about a quarter of a 
mile southwest of the Ben Butler, on an approximately parallel lode, 
had a shaft 50 feet deep in 1899. The vein is in two main branches, 
