TEEAT.MEXT OF SULPHUEET OEES AT CIIABACTEEISTIC MIXES. 145
at the Tan-yard deposit; and pyrophyllite occurs as an alteration product in rhe granitic dikes.
The ore itself is practically devoid of auriferous vein-quartz. Small reticulated fissures filled with barren quartz intersect the country; and in the Tan-yard (an old gravel-channel to the east of the mine) a large barren quartz-vein, 5 to 20 feet in thickness, is to be seen.
The Brewer mine, probably one of the first developed in South Carolina, was opened in 1828 by shallow pits in the saprolites and in the gravels of the Tan-yard, the material being worked in rockers. This work continued until 1857, and it is stated that in various years during this period as many as 100 to 200 hands were employed at one time, making $1.50 to $3 per day each, and paying nearly 30 per cent, royalty. From 1857 to 1802 Commodore Stockton mined and milled the ore in arrastras and Chilian mills. Up to 1879, when the Brewer Mining Company took hold of the property, there seems to have been a lull in the activity of the operations. In this and succeeding years the old Tan-yard placer was reworked by hydraulicking. This deposit is an old river-channel, and was extensively worked in former days, being, in fact, the site of the first discovery of gold on the property. The widtli of the channel is from 200 to 300 feet, and its length about 1-J miles; it is now intersected by a large valley. The original overlay was about 0 feet, and the gravel from 3 to 6 feet in thickness, underlain by a thin bed of compact conglomerate, cemented by iron oxide; the bedrock is a siliceous sericitic schist. The old miners in working this ■deposit did not wash the overlay, nor did they take up any part of the bed-rock. In reworking, the whole mass (from 5 to 20 feet in thickness) was hydraulicked, and as much as 4 to 5 feet of the loose bed-rock was also torn up. Water was pumped about 200 feet in vertical height, from Lynch's creek to a small reservoir situated at the head of the placer, from where a portion of it was delivered to the giant (2^-inch nozzle), by a force-pump under a pressure of SO pounds, and the remainder run directly through the ground-sluices to carry off the tailings. Six men were employed in cleaning bed-rock, and two at the sluices. It is stated that a handsome profit was realized by this work.
In 1885 a 5-stamp mill was erected and run on ores produced in prospecting work. In 1.887 an adit-level (A, fig. 31), 1200 feet in length, was driven into the hillside under the main ore-deposit, and the mine was opened from below by a raise, which was at the same time used as a chute, connecting with the open pit above. The stoping was carried on overground, and the material taken out through the tunnel. In 1888 a 40-stamp mill was erected, and started up in May, 1S89. A Thies clilorination plant was added in 1892, and operated for a short time during 1S93. From that date until June, 1895, the mine was idle,
hut at that time preparations were being made for starting work again. 10