GEOLOGY. 61 
Wood and water are very scarce. Little is known about the 
district as yet. The Coso and the Esmerelda districts are both 
in the Great Basin of Utah, and about five thousand feet above 
the level of the sea. 
It is said that rich silver-mines have been discovered in the 
valley of the Mojave River. 
In the Coast Mountains, in Monterey county, a silver-mine 
called Allisal has long been known to exist, but it is not rich 
enough to pay. Similar veins are found in the Coast Moun- 
tains, in Santa Cruz county. 
Veins of silver ore are also found in Nevada county. 
§ 41. Platinum. —Platinum, i iridium, and osmium, are three 
white metals resembling steel, often found in the placer mines 
of California. They usually occur together; and are found 
more abundantly in the lower part of the Klamath valley than 
in any other part of the state. In many districts they are 
entirely lacking. Platinum is found in lumps by itself; iridi- 
um and osmium are found united, and are then called irid- 
osmium. These metals are found in small particles, usually 
fine scales; the largest piece was of irid-osmium, found on the 
Lower Klamath, and weighed an ounce and a quarter. They 
are not found separate from the gold, nor are they ever the 
main object of search; they are obtained in small quantities 
only, and are rarely bought and sold in the state; they have 
no fixed market price. When mixed with gold-dust, they 
injure its value, and prevent its reception at the mint on de- 
posit. 
§ 42. Quicksilver—There is probably no country in the 
world so rich in quicksilver as California. That metal is ob- 
tained only from its sulphuret or cinnabar, of which extensive 
deposits are found in Santa Clara county, aboug sixty miles 
southward from San Francisco, and fifteen miles from San 
José. There are three mines here—the New Almaden, the 
Enriqueta, and the Guadalupe. The ore is found between trap 
on one side, and metamorphic limestone on the other. The 
mines are about one thousand feet above the level of the sea. 
