130 SOUTHWESTERN NEVADA AND EASTERN CALIFORNIA. 
substance is usually opaque, but some is slightly translucent. The 
chrysocolla is commonly massive, locally with a botryoidal structure, 
and in some massive phases an occasional cleavage face is seen. It 
is cut by veinlets of manganese dioxide and white calcite or quartz. 
Chrysocolla veinlets of slightly different color cut one another, 
showing that the formation of this mineral extended over a consider- 
able period. Associated with it is a crystalline, bottle-green, semi- 
transparent mineral whose cleavage faces reach a length of one-hall 
inch. A radial structure is observed in places. This mineral is 
embedded in the chrysocolla or cuts it in veins and is of practically 
contemporaneous age. It is probably brochantite, a hydrous sul- 
phate of copper. Both the chrysocolla and the brochantite were 
determined by Mr. Waldemar T. Schaller. Postminera] faults cut the 
veins and parallel them. Pieces of blue chrysocolla closely resemble 
turquoise, and several hundred pound- of the material have been sold 
for this gem. The mineral takes an excellent polish. The largest 
piece of pure chrysocolla seen was ('» by 3 by 2 inches. 
In these copper deposits the minerals exposed are all secondary. 
Malachite, chrysocolla, brochantite, cerussite, a jaspery quartz, and 
limonite seem practically contemporaneous. There is considerable 
evidence that the formation of the copper minerals and the jaspery 
quartz extended over a considerable period, during which some frac- 
turing occurred and in consequence the relations between these min- 
eral- arc complex. They partly replace the limestone and partly fill 
fissures. Azurite, emmonsite, quartz, and calcite are of later origin. 
Narrow seams and veins of quartz are rather widely distributed in 
the Pennsylvanian rocks, particularly near granite intrusions. In 
the slaty shales and quartzites throughout the southern portion of the 
range such veins occur. A quartz vein 2 inches thick which carries 
some pyrite cut- the shale one-half mile south of WTiiterock Spring. 
Specimens of quartzite, which evidently came from the quartzite to 
the north, were found at Tippipah Spring. These were rather 
strongly stained by malachite and hematite. 
Oak Spring furnishes sufficient good water for domestic purposes, 
rnd there are several other springs in the general vicinity. Oak 
Spring Butte is timbered to some extent. Calientes, on the San 
Pedro, Los Angeles and Salt Lake Railroad, is the natural shipping 
point. 
OTHER AREAS. 
Prospects are located on either side of the road from Kawich to 
Cliff Spring, near the eastern border of the Pogonip limestone. The j 
supposed ore is in part a fine-grained quartzite and in part vein 
quartz, in which are small disseminated iron-pyritc cubes and thin 
stringers of pyrite. The veins where examined are thin. 
