Report of the State Mineralogist . notenough has been done to give any hint of the possible amount of oreavailable. The sulphides have been completely leached out of the out-crop. So-called dikes crossing the vein appear to be pyritized zones inthe amphibolite and may have influenced mineralization of the vein. On the east slope of the hill about \ mile due east of the above thereis a parallel vein of quartz as much as 18 ft. wide in places, which hasbeen opened by a 200 ft. shaft, now caved, and a shaft 40 ft. deep con-nected with a crosscut to vein. Farther south are several short tunnels El
Report of the State Mineralogist . notenough has been done to give any hint of the possible amount of oreavailable. The sulphides have been completely leached out of the out-crop. So-called dikes crossing the vein appear to be pyritized zones inthe amphibolite and may have influenced mineralization of the vein. On the east slope of the hill about \ mile due east of the above thereis a parallel vein of quartz as much as 18 ft. wide in places, which hasbeen opened by a 200 ft. shaft, now caved, and a shaft 40 ft. deep con-nected with a crosscut to vein. Farther south are several short tunnels Ely DORADO COUNTY. 431 in bad shape showing possible ore on the dumps, the best of which wasoutside a caved tunnel about which nothing could be learned. There isno machinery or equipment on the property, and only one small dwelling. CHROMITE. Placer Chrome Company Plant, is located near Rattlesnake bridge,7 miles from Newcastle. This companys old mill, described in ourBulletin No. 76, was finally dismantled and abandoned in February. Photo No. 55. Quarry and loading plant at Mountain Quarry property of Pacific PortlandCement Co., on Middle Fork of American River in El Dorado County. 1920. A new mill building was put up at the foot of the1700 ft. gravity tramway, and part of the machinery from the oldmill was put in it. Milling began in January or February andcontinued till November, as orders came in; plant closed in reduction equipment consists of gyratory crusher, Hendy 50-tonball mill, 4 Overstrom concentrators and a small ball mill to regrindmiddlings. Electric power was used. The ore as mined averaged about15% Cr203 and the plant turned out about 5 tons of concentrate a day 29—8725 432 MINES AND MINERAL RESOURCES. when working, but was only operated when orders were received. Tenmen were employed when running full handed. Concentrate ran 50%Cr203, or better, and was used a good deal for chemicals and was hauled to Newcastle at a cost of $ a
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectminesandmineralresou
