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DISTRIBUTION OF GOLD METES IN NORTH CAROLINA. 55
a sheet of greenstone about 3 feet thick, and that it is underlain by another auriferous gravel deposit, which may be considered virgin ground, as no attempt has yet been made to work it. There would be no great difficulty in getting a sluice on the bed-rock beneath this lower grit, with sufficient fall to carry off the tailings.
The hydraulicking plant is very extensive. It consists of a Worthington compound duplex condensing pump, with two 100 H. P. boilers (using 7 cords of wood per day, at $1 per cord), situated on the Yadkin river, 4J miles from the stand-pipe at the mine, and 340 feet below the same. The pipe-line on the lower lift is 20 inches in diameter, flangeriveted, made of fj-inch steel; on the upper lift is a similar steel pipe 12 inches in diameter. Expansion-joints are placed every quarter of a mile, and the full length of sleeve (8 inches) is necessary to take up the maximum expansion and contraction of the pipe caused by changes of temperature. The capacity of the pump is 1,500,000 gallons in 12 hours; the head furnished from the top of the stand-pipe to the mineworkings is about 90 feet. (Plate V.)
Besides the gravel channels at the Parker, the saprolites are, in general, auriferous; and a combination sluicing and milling process (Dahlonega method, see p. 107) was at one time attempted here. The bank was undercut with powder and the shattered mass moved with the giants. The material ran about 50 cents a ton in the mill; but only a small percentage of it was quartz, and an attempt to select the latter proved unsuccessful. The tailings in the mill were reasonably low; but the loss of fine gold in the overflow from the mill-tank, in connection with the exhaustion of the richer available saprolites, led to the abandonment of the process.
The mill is a 10-stamp one, built by the Mecklenburg Iron Works of ■Charlotte, 1ST. C. The weight of the stamps is 650 pounds. In the Dahlonega practice 4 drops were given 80 times per minute, and round punched screens were used; there were no inside plates. About 50 per ■cent, of the gold was saved in the mortars between the dies. The total •cost of milling (including 1 cord of wood at $1), with 1 hand on each shift at $1, was $4 per 24 hours.
The last work done at the Parker (fall and winter of 1895) was that of prospecting some of the larger quartz-veins on the property. The Poss shaft was sunk to a depth of 130 feet and a vein was opened by a erosscut, showing sulphurets of iron and copper in white quartz, which gave assay values ranging from $3 to $12 per ton. The same vein had been exposed in a 130-foot shaft to the west of the Poss, where assays of the quartz showed values of $3 at the 85-foot and $7 at the 130foot level.
The dimensions of the Ross shaft are 5 feet 6 inches by 11 feet inside
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