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Show 53 The walls are slickensided, and there are other indications of a true fissure- vein. It dips at an angle of 82°. Its strike is northeast, directly perpendicular to the bedding of the country- rock. The rock is primitive, granite and syenite. The mineral constituents are very irregniarly scattered. Sometimes they are almost purely quartz and feldspar, and again are chiefly hornblende, or mica, schist. The native metals alone are collected. This is done by amalgamation in stamps. The average yield per ton is about $ 22. The bullion obtained is an alloy of gold and silver, one part silver to two parts gold, whose average worth is $ 14 per troy ounce. Water leaks in at various levels, especially at the lowest, which is 280 feet below the surface. No change has been observed in the character of the ore, which is a compact quartz, containing native gold and silver, with which are mixed sulpha-rets of arsenic and antimony, and pyrites in small quantities. As it comes from the mine, the ore is mixed with clay and country- rock from the horses and walls. The vein- rock is but little decomposed, The native metal can occasionally be distinguished with the naked eye. The snlphurets occur both in specks and in masses of considerable size. About $ 150,000 has been expended on the Bright Star Mine, from which 1,200 pounds troy of bullion, valued at $ 14 per ounce, have been taken. Its ores are worked by one mill, with three batteries of five stamps each, which make 85 drops per minute. The entire mill is run by one small engine of 35- horse power. There is a great scarcity of water, the only source of supply, aside from two or three small springs, being the mine itself, which furnishes enough for the engine, the stamps, and culinary purposes. The sulphurets have not been treated yet, but are allowed to accumulate and await the completion of a furnace in which they may be roasted. The cost of a 10- stamp mill on the grounds is abont $ 6,000. Other expenses will average as follows: Cost per ton for mining ore, $ 2; for reducing the same, $ 2; mining labor, per diem, $ 3.37; milling labor, $ 4; running a tnnnel on main vein, per foot, $ 6; siuking a shaft, $ 12; running a drift, $ 6. One man will stope two tons of ore per day. There is but little farming- land in tlTe immediate vicinity, and but few cattle or other stock. The present sources of supply are Kernville, Havilah, Kelso Valley, and small valleys in the mountains. Grain is worth 5 cents per ponnd; hay, $ 25 per ton. The mine is surrounded by very heavy pine timber. Deer and quail abound. CLARKE DISTRICT, CALIFORNIA. Examined by Dr. O. Loew, July, 1S75. The Clarke Mountain, near Ivanpah, is a part of the Opal Mountains. On both sides of this, but especially on the eastern slope, are the mines of the Clarke district, whose croppings cover an area of great extent. This district was discovered in 1869, was organized in 1870, and has been constantly worked since. Its post- office is Ivanpah. The nearest railway town is San Bernardino, which is 200 miles distant, via Soda Lake and the Mohave River. Cost of freight from this point is 5 cents per pound. The mines were previously examined by Lieutenant Wheeler in 1871. The direction of the lodes is east and west, transverse to the general trend of the district. Quartzite and paleozoic limestone form the wall-rock; the vein- matter is quartz, and, in some instances, calcspar. In AP. JJ- 4 |