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124
GOLD MIXING IX GEORGIA.
care of the water. At the surface, the ore is run over a grizzly and then through a crusher, the jaws of which are set \}j inches apart. The crushed ore is hauled to the mill by mules in cars of 1.1 ton- capacity, which are loaded from a bin below the crusher.
During the summer and fall of 1S95 two other shafts, Xo. 3 and Xo. 4, located respectively j and f miles southwest of Xo. 2. were in progress of sinking, with the object of developing in depth lenses of ore which had been located and worked to some extent on the surface. Considerable diamond drilling has been done on the property (-ume 800 feet in all) at a cost of about $1.25 per foot.
The mill is situated about ~l of a mile from Xo. 2 shaft, on the east bank of the Etowah river. AVater at a head of 7-J- feet is supplied to two turbine wheels by a dam thrown across the river. One of the turbines, a 60-inch Leffel wheel, supplies 23 horse-power to the stamp-mill, while the other, a 56-inch Davis wheel, drives a duplex "Rand iiu'-enmpressor. The concentrators are run by steam-power, that derived from the turbine not being of sufficient regularity to secure a uniform product. There are 20 stamps in the mill, 10 of AVestern make and 10 erected by the Mecklenburg Iron AVorks. Weight of stamps 850 pounds, 7-inch drop, 70 drops per minute, 6-inch discharge. Xo inside plates arc used and no quicksilver is fed to the battery (a little coarse gold i- cleaned from the battery sands). The screens are Xo. 7 slotted Kussia iron, corresponding to about 30-mesh. The outside plates have the full width of the mortar. They are 8 feet long, arranged in four steps, and are handled in the same manner as those at the Haile mine. About 55 per cent, of the gold extracted from the ore is saved by amalgamation. The ore is fed from bins by Hendey automatic feeders. The mill handles 35 tons in twenty-four hours.
The pulp from each 10 stamps is carried by launders to four hydraulic classifiers, the overflow from all these going to one slime-spitzkasten of 9 by 9 feet surface dimensions. The product of the 8 hydraulic classifiers goes to 8 Embrey tables, the product of the slime-hasten being distributed to 2, making 10 tables in all working on mill-pulp. Besides these, there are 3 tables working on old amalgamation tailings, assaying about $3 per ton. The concentrates are not (dean, containing about 50 per cent, of sand, but close work would decrease the percentage of extraction. The average amount of sulphurets in the ore mined is about 5 per cent., sometimes running as high as 9 per cent. As high as 5^ tons of raw concentrates are produced and treated in twenty-four hours. The tailings from concentration run at present about 85 cents per ton, giving a remarkably high percentage of extraction.
The concentrates are roasted in two double-hearth reverberatory furnaces, with a capacity of 2 tons of roasted ore each in 24 hours. Twelve
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