Elements of mining geology and metallurgy (illustrated); a practical field and office manual, and reference compendium, treating on the geology of mining metallurgical methods of western America

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1906 Excerpt: ...(Fig. 119, H). By this means the cars may be dumped directly into the tanks; the ore is then leveled with a hoe. Art. 338. A method of distributing the ore into the tanks, which produces a more even percolation than the above, is to discharge the contents of the cars into a hopper centrally located. In connection with this hopper is an adjustable spout, by means of which the ore is directed to any part of the tank desired. Art. 339. It is imperative in leaching operations that no portion of the ore shall permit of an easier passage of the solution than the other portions, and the adjustable spout method of distribution is therefore recommended as producing a bed of ore of equal density throughout. The tank is now ready for the cyanide solution. CASE (B)--PREVIOUS CRUSHING AND AMALGAMATION FOLLOWED BY CYANIDING. Art. 340. Stamp Mill Crushing.--Where from 50 to 75 per cent of the gold in an ore can be saved by amalgamation, and the remaining va'ues in the tailings and sulphurets recovered by cyaniding, the usual practice is to employ the regular stamp-milling process, with concentrating tables, followed by a cyanide plant situated below the stamp mill b ilding. Art. 341. In this case, the methods employed for filling the leaching tanks with the battery tailings ic somewhat different to the preceding. Two methods are in general use: (1) Intermediate filling, and (2) direct filling. The object aimed at in either method is to fill the tanks so as to uniformly mix the sands and reject the slimes, so the ore will be sufficiently porous that it will admit of free percolation of the cyanide solution. Art. 342. Intermediate Filling.--Where intermediate filling is employed, a device known as the Butters & Mein's automatic revolving distributor is in common use (Fi...