Mineral Deposits of Eastern Calif ornia. — Fairbanks. 145 
veinlets of quartz which appear prominent on weathered sur¬ 
faces. No gold is found in these but in five fairly regular 
veins from a few inches to two feet in thickness. The ore is 
high grade, the gold being present on the surface in the free 
state, but judging from the appearance of the quartz it was 
originally contained in iron pyrites. 
A large number of gold bearing quartz veins are scattered 
through the southern portion of the Argus range. They are 
inclosed in a great body of granite which extends from San 
Bernardino county north through the Coso mountains to 
Owen’s lake. The deposits are being worked in a number of 
places and appear to be quite rich. The character of the 
quartz makes it seem probable that some distance below the 
surface most of the gold will be found contained in iron py¬ 
rites. Chalcopyrite and galena are abundant in some of the 
veins and carry considerable silver. 
With the exception of numerous areas of volcanic rocks the 
Coso mountains consist wholly of granite, the mineral depos¬ 
its being confined to the latter rock. The quartz veins are 
characterized by the presence of free gold on the surface, 
while at depths varying from 250 to 400 feet the free gold 
has been found to be largely replaced by iron pyrites with a 
subordinate amount of chalcopyrite. 
The Beveredge go}.d district is situated on the eastern slope 
of the Inyo range at an elevation of 5,000 to 8,000 feet. The 
veins are confined to a large body of granite which has broken 
through the metamorphic series. Many of the veins are nearly 
vertical while others are quite flat, dipping 20 degrees or less, 
and being locally known as blanket veins. The mine which 
has been worked the longest and most steadily is known as 
the Keynote. A depth of 700 feet has been reached on the in¬ 
cline and the ore, which was free milling on the surface, has 
been found with increased depth to contain a greater propor¬ 
tion of iron pyrites and chalcopyrite. In the American Flag 
mine at the southern end of the district gold is found associ¬ 
ated with galena and even imbedded in it. The Chilula mine 
lies partly in limestone and partly in granite. The portion of 
the vein in granite carries gold, but upon passing into the lime¬ 
stone the gold is replaced by silver ores. This seems to be a 
good illustration of the physical influence of the wall upon 
