The Hamme tungsten district is in the eastern part of the Piedmont province, mainly in Vance County, North Carolina, but it extends a few miles into Virginia. The district is underlain by a central lenticular pluton of albite granodiorite that trends north-northeastward and is flanked on both sides by metamorphic rocks of low and medium grade that dip steeply westward. The relative ages of the metamorphic rocks are uncertain. The oldest rocks are likely to be the blotite gneisses in the eastern part of the district; successively younger units exposed westward across the district are sericite-chlorite phyllltes, greenstone, metafelsites, and metabasalts.
General geologic mapping of the district by the U.S. Geological Survey, the basis of the present report, was begun in August 1949 and continued during the summers of 1950-53 inclusive by the writer with various field assistants and between January 25 and March 1, 1954, by M. H. Staatz. During these periods a total of about 9 months was snent in the field. By John M. Parker, III, 1963. 69 pages. Includes 2 plates.
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