ORE DEPOSITS OF THE REGION 676 



places. Genth and Kerr * mention the following copper minerals occur- 

 ring in Person and Granville counties: chalcopyrite,chalcocite, malachite, 

 chrysocolla, cuprite, and native copper. Chalcopyrite and pyrite are 

 almost entirely absent from these veins. They were observed in largest 

 amount at several shafts being opened on the High , Hill property in 

 Virginia at the time of the writer's visit. 



So far as examined, the ores are free from arsenic and antimony, but 

 are reported to carry, at times, very appreciable traces of both gold and 

 silver, particularly the latter. The following assays of the gray ore from 

 the Yancey mine in Person county, North Carolina, are given by Hanna, f 

 and serve to illustrate the values of the mineral material. 



Gold, per ton, -^ ounce, y 1 -^ ounce, -^ ounce. 



Silver, per ton, 6^ ounces, 5^ ounces, i ounce. 



Copper, per cent, 48.17 26.16 31.14. 



In the Holloway shaft, 3.5 miles south of Virgilina, the vein has been 

 opened to a depth of more than 500 feet, and the action of the percolat- 

 ing carbonated waters is shown to this depth in the occasional presence 

 of the green carbonate, malachite, in association with the unaltered ores. 



The particular interest in the ore deposits of this district is the some- 

 what analogous occurrence and association in many respects of the cop- 

 per minerals, including native or metallic copper, in the greenstones 

 (originally igneous in origin) to certain closely allied areas of altered 

 igneous rocks of the Lake Superior region, and the Catoctin and South 

 mountain areas of Virginia-Maryland-Pennsylvania, and to other smaller 

 and less important areas in Virginia and North Carolina. Furthermore 

 the association of the copper with epidote is not only true of the Vir- 

 gilina belt, but is described by various geologists J as true to some degree 

 for the other areas of the Atlantic Coast and Lake Superior regions. No 

 indications of amygdaloidal structure so common in the rocks with which 

 the copper is intimately associated in many of the other areas is found 

 in the Virgilina district. 



In describing the general distribution of the Catoctin type of copper 

 deposits, Weed says : 



" It is evident that the association of epidote (and, to a lesser degree, of chlorite) 

 and the native copper is a constant one, for which reason it is believed that the 

 processes incident to the formation of the one led to the formation of the other. 

 Such ores occur near Virgilina, Virginia, near Charlotte, North Carolina, and in 

 many scattered localities through the South." $ 



*The Minerals and Mineral Localities of North Carolina, Raleigh, 1885, 128 pages; also Bulletin 

 no. 74, U. S. Geol. Survey, 1891, pp. 98, 109. 

 fOp. cit., p. 220. 

 % Op. eit. 

 I Trans. Amer. Inst. Min. Engrs., 1891, vol. xxx, p. 503. 



