Mineral resources of the United States . harder and harsher whiteaccompanying material, which is apparently fibrous tremolite. Thedeposit has been much squeezed and sheared, developing slickensideslike plastic clay, which are generally parallel to the dip. On the sidetoward the diorite there is much faulting, and masses of tremoliterock are caught in the talc. Nodules of serpentine, and also ofcalcite and tremolite, from the size of a nut up to sheets a foot inextent, occur in the talc, and they have to be carefully removed. Thesheets of calcite are usually bent or crumpled, as in highly cryst
Mineral resources of the United States . harder and harsher whiteaccompanying material, which is apparently fibrous tremolite. Thedeposit has been much squeezed and sheared, developing slickensideslike plastic clay, which are generally parallel to the dip. On the sidetoward the diorite there is much faulting, and masses of tremoliterock are caught in the talc. Nodules of serpentine, and also ofcalcite and tremolite, from the size of a nut up to sheets a foot inextent, occur in the talc, and they have to be carefully removed. Thesheets of calcite are usually bent or crumpled, as in highly crystaUinerocks, and many of them have a decided tendency to cross-fiberstructure. This deposit occurs in an arid, treeless country at an altitude oi2,300 feet—about 1,000 feet above the railroad, to which there is a7-niile wagon haul; and more than 2,000 tons of talc have beenremoved within the last few years. The occurrence of talc on Sheep Creek 20 miles northwest of SilverLake is illustrated in figure 5. The irregularity of the contact. TUNNEU 0 Figure 5.—Section of talc deposit and adjacent rocks on Sheep Creek, 20 miles northwest of Siher Lake,Cal. t, Talc; b, banded limestone; s, sedimentary rocks, inlcuding crystalline limestone, quartzite, andhomfels, the result of contact metamorphism; d, diorite. between the diorite and the sedimentary rocks, as well as the contactmetamorphism apparent in the hornfels, indicate that the diorite islater than the sedmientary rocks and may have been a factor in thegenesis of the talc, which follows the contact between the diorite andthe limestone. Grayish limestone occurs more or less abundantly inthe talc—to an irregular thickness of nearly 30 feet. The strike of thedeposit is northwest and southeast, and prospects have been openedalong the outcrop for half a mile. Other prospects are reported on thesame strike 6 miles farther to the northwest. At all the prospectsseen the workings run into the talc horizontally. No evidence wasseen t
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Keywords: ., bookcentury1800, booksubjectmineralindustries, booksubjectminesa
