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Ch. 5: Mine & Milling Practice

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114                                             GOLD MIXING IN GEORGIA.
basis. Despite many inquiries amongst local mill-men and others, we could hear no reports of losses in amalgamation resulting from so-called rusty gold. A loss of this nature was in a few cases ascribed to the finely-divided or flaky condition of the gold.
It is difficult to give any average values of the Dahlonega ores, or in fact to clearly designate exactly what the term ore applies to in this district. Material worth as low as 40 cents per ton has been milled at a profit. If this figure per ton, plus the gold saved in the sluices (20 cents per ton milled) represents the milling-value of 5 tons of material mined, as is stated to be frequently the case, then the value of the latter per ton must have been 12 cents. As a rule, however, the mill-stuff is of better grade than the above. The actual ore (quartz) is stated to assay from $1 up to exceptionally high values in the cases of rich stringers or pockets.
The cost of mining and milling throughout the district will average from 18 to 25 cents per ton of ore milled.
A description, somewhat more in detail, has been prepared of the following mine as representing perhaps most perfectly the Dahlonega method in its original type (of working soft saprolites or highly decomposed material).
DAHLONEGA METHOD AT HEDWIG JUNE.
The Hedwig mine is situated near Auraria six miles west of Dahlonega. It consists of a large open cut about sixty feet in depth, run on a line of siliceous, micaceous ore-bearing schists, sixty feet in total width. The strike of the schistosity is S".E. and the dip 60° S.E. Three separate ledges of barren hornblende-gneiss (brickbat) enclose two ore-bodies, striking and dipping conformably to them. But very few small quartz-stringers occur in the mass. "Water is furnished to the giant (3-inch nozzle) under a maximum head of GO feet from a reservoir situated on the hillside above the mine. Six men are employed at the mine at 8-0 cents per day (day-shift only).
The material is run to the mill in a flume 2800 feet in length and 14 by 16 inches in cross-section, made of oak boards. It is supplied with longitudinal riffles made of 2 by 3-inch post oak scantling. The grade of this sluice is 4f inches in 12 feet at the lower, and 3? inches at the upper end, that is, in the cut where it is not necessary to avoid overflows. The outside mill-bin holds about 240 tons, and the material is flushed from here to the inside bin, which holds 200 tons. Formerly there were three outside bins and the ore was hauled to the mill in cars.
The mill is a 40-stamp one of the Hall pattern, with a 12-foot driving pulley. It is driven by a 4-inch Ridgeway wheel, using 40 inches of water from two 1-inch nozzles. The water is supplied from the same
Ch. 5: Mine & Milling Practice Page of 172 Ch. 5: Mine & Milling Practice
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