GOLD MOUNTAIN RIDGE AND HILLS NEAR BY. 
This rock, like some of the basalt of the Panamint Range, is spotted 
by areas of lighter color. The phenocrysts, which are small and 
fairly abundant, include striated feldspar. g 
glassy green olivine, and blackish-green pyrox- 
ene. The basalt breaks down into rounded 
bowlders heavily stained by iron oxide. It is 
later than the rhyolite and is probably contem- 
poraneous with the basalt of Slate Ridge and 
Mount Jackson and of late Pliocene or early 
Pleistocene age. 
STRUCTURE. 
The Cambrian rocks dip steeply away from 3 
the granite batholith, and near-by faults and £ 
brecciation, isoclinal folds, and buckled strata I 
are developed. (See fig. 16.) At a distance | 
from the granite the dips become less pro- % 
nounced, but the mass of granite is so large and | 
the Cambrian masses so small that rather high | 
dips are characteristic throughout them. The g 
granite is cut by fault and joint planes. Prior £ 
to the outflow of the rhyolite and basalt the | 
granite and Cambrian rocks had a topography £ 
somewhat less rugged than at present, but the q 
Gold Mountain ridge appears to have existed. £ 
Blocks of rhyolite north of Grapevine Canyon - 
are tilted in different directions by normal £ 
faults, the majority of which strike northeast e, 
and southwest. § 
ECONOMIC GEOLOGY. 
o 
The Gold Mountain mining district, organ- | 
ized January 25, 1868, embraces within its lim- 5' 
its the Gold Mountain and Slate ridges. Mines g 
have been worked in the district intermittently 1 
since that time, and several mills have been 
built, none of which are now in operation. Old 
residents estimate the total product of the dis- 
trist as $500,000, the concentrates being hauled 
by w T agons to Belmont and Austin, Nev. The 
mines and prospects lie in the more highly met- 
amorphosed Cambrian rocks and in granite, 
and these rocks in this vicinity are probably 
most favorable for prospecting. The contact 
of the rhyolite and granite 9 miles south of west of Gold Mountain is 
in places altered to an iron-stained, incoherent mass, cemented by 
chalcedonic quartz, and this contact is perhaps worthy of examination. 
SJU* * 
