A geochemical reconnaissance of some gold mines in the gold-pyrophyllite belt of northwestern Moore County, N.C. (fig. 1), suggests that the rocks and saprolite of the area contain small but anomalous quantities of gold (figs, 2 and 3). Out of 244 rock samples collected in an area 35 km long and 10 km wide, 190 contain gold in amounts ranging from 0.02 to 2.40 parts per million (ppm), and 48 contain gold in amounts that are detectable but below the limit of determination, which is 0.02 ppm (figs. 3 and 4; table 1). The median concentration of gold in all samples is 0.04 ppm; only 12 samples, 5 percent, contain 0.9 or more ppm. The median concentrations of gold in various types of samples are given in table 2. The highest concentration of gold in the samples analyzed, 2.40 ppm (sample no. 193), is from a composite of three quartz veins, 1 to 2 cm thick, exposed in a roadcut about 0.4 km from the nearest known gold mine.
Traces of gold and molybdenum are widely disseminated in an area approximately 35 km long and 10 km wide in northwestern Moore County, N.C. At least 2540 oz. of gold were recovered from 16 or more mines and prospects between 1880 and 1910. One hundred and ninety rock samples out of 244 collected from old gold mines, pyrophyllite deposits and along roads contain gold in quantities ranging from 0.02 to 2.4 parts per million. In addition, 43 samples out of the 244 taken contain molybdenum in amounts ranging from 4 to 500 parts per million.
By Frank G. Lesure, 1981. In black and white. Map size approximately 50"x40".
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