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Amalgam is retorted and melted in the usual manner, the grade of the resulting bullion being 357 to 535 fine in gold, and 10 to 15 parts of base metal.

In the cyanide work, the first and second compartments of the strong boxes are cleaned up in the middle of the month and a complete clean up of all the boxes is made at the end of the month. The rich slime goes straight to the vacuum filter boxes, and the other slime is washed on a 30 mesh sieve to remove shreds of zinc before being filtered. After draining under vacuum, the slime is dried and oxidized at a dull-red heat, the floor of the furnace being an iron plate heated from below. The roasted slime is cooled and mixed with soda carb. (soda ash), 6%, crushed borax glass, 30%, and fluor, 1%, melted in two tilting furnaces and poured into conical moulds. The bullion is usually free from mate. It is re-melted in crucible furnaces with a little borax, the slag is skimmed of (thickened by a little bone-ash if necessary) and the bullion cast into bars of approximately 1,300 ounces. The fineness is from 52 to 146 in gold according to the ore treated, and from 50 to 60 of base metal. The bars are about 4½ inches thick and are sampled by drilling two holes, one at the top and 1/6th of the length from one end, and the other at the bottom and a similar distance from the other end. The holes are drilled 1½ inches deep and the outer crust is discarded. The clean-up slag is broken up and then crushed without amalgamation in a 2 head (Union Iron Works) stamp mill of 400lb. head. The pulp goes to a Berdan pan and from there to settling pits. The amalgam from the Berdan, and shot metal from the mortar box, are returned to be smelted and the crushed slag is dried and shipped to the smelter, being worth about £30 per ton.