AMARG0SA RANGE, ECONOMIC GEOLOGY. 
Bismuth mine is situated on the road to Bullfrog, somewhat below the 
Chloride Cliff mine. The quartz, which is heavil stained by limon- 
ite, contains finely granular galena. The presence of some malac] 
probably indicates the former presence of chalcopyrite with the pyrite 
and galena. 
lee's camp. 
Lee's Camp is situated in the Cambrian rocks, 10 miles southwest 
of Rose's Well. The camp was not visited by the writer, but strong 
veins of quartz are said to exist there. The ore, which is said to mill 
free gold, is quartz and either dolomite or siderite, each heavily 
stained by limonite. 
AREAS FAVORABLE FOR PROSPECTING. 
Quartz veins are common in the metamorphosed Cambrian sedi- 
mentary rocks. They occupy joint and bedding planes and fault 
fissures, and in the latter case may contain angular fragments of the 
Cambrian rocks. In size they vary from mere stringers to veins 6 
feet or more across, which can be traced for hundreds of yards. In 
the vicinity of Poison Spring these are particularly strong, and over 
restricted areas make up almost one-third of the rock. The quartz 
in most instances is white and semitransparent and appears barren. 
In others it has been faulted and brecciated and is stained by limonite, 
while p3^rite and specular hematite are disseminated in it here and 
there. The mines of Echo Canyon, to the south of the area surveyed. 
are reported to be situated on similar quartz veins. Pyrite and 
hematite also occur in quartz veins on the small Cambrian hills to 
the northwest of the Big Dune, and these minerals and malachite are 
found in the quartz veins of the big Cambrian inlier to the southwest 
of the Big Dune. 
In the Pogonip limestone of the central and northern portion of 
the Amargosa Range quartz veins are of minor importance. The 
veins, some of which contain pyrite and specular hematite, appear to 
be comparatively small. About G miles south of the Staininger ranch 
prospectors sunk a shaft 10 feet deep on a quartz vein stained with 
malachite. At this depth the vein divided into several stringers and 
the shaft was abandoned. The ore carried low gold and silver values. 
With the change of the country rock from the siliceous deposits of the 
Cambrian area to the calcareous rocks of the Silurian and Ordovician. 
calcite veins, probably in part contemporaneous with the quartz veins, 
become predominant. These are extremely abundant, but as a rule 
are less persistent and less mineralized than the quartz veins in the 
Cambrian. At Titus Canyon the calcite veins are of two ages. The 
older are formed of white crystalline calcite, much of which is very 
coarsely granular. The younger veins, of banded yellow or brown 
