. Economic Papers. whichhas a varied dip and strike where it is cut by the tunnel. Several feet be-fore the vein was reached the tunnel encountered coarse granite or fine-grained pegmatite, which grades into coarse pegmatite near the coarse granite cuts across the schistosity of the gneiss, which trendsN. 15° W. and has a 25° W. dip at the contact, whereas the granite has astrike more nearly east and west. Figure 20 shows the position of theworkings and the relations of the rock formations. The crystallization of MINING INDUSTRY. 59 the pegmatite as exposed in the walls of the drift i
. Economic Papers. whichhas a varied dip and strike where it is cut by the tunnel. Several feet be-fore the vein was reached the tunnel encountered coarse granite or fine-grained pegmatite, which grades into coarse pegmatite near the coarse granite cuts across the schistosity of the gneiss, which trendsN. 15° W. and has a 25° W. dip at the contact, whereas the granite has astrike more nearly east and west. Figure 20 shows the position of theworkings and the relations of the rock formations. The crystallization of MINING INDUSTRY. 59 the pegmatite as exposed in the walls of the drift is very coarse. Crystalsof orthoclase feldspar 2 and 3 feet square had been cut through and thecandle light reflected from the cleavage faces exposed outlined their shapeswell. This mine is reported to have yielded large blocks of mica, one weigh-ing about 2,000 pounds. Samarskite is said to have been found in massesof many pounds weight and broken up and lost before its nature was known. PegmatiteDrift and stope. Figure 20— Plan of the later workings at the W. W. Wiseman mine,Mitchell County, N. C. Charlies Ridge Mine—The Charlies Ridge mine is 1V2 miles south ofwest of Plumtree and one-half mile west of Spear, about 200 yards south-
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