Show CAN CAK CA WORK 1 TAILINGS S Method Suggested of Recovering Gold Prom From r Mill Hill Dumps S Henry HeIllY M AI Crowther the well known I engineer nc metallurgist as a aa asa S a a n most Interesting article in n the last laste e issue of the u 1 Mining Journal on n h be possibilities of working workingS C over oyer tailings from the big cyanide mills S S at a profit even where the values ran rana a low a 1 l to per ti The article wae suggested by a aries anes Aeries of tests which he recently conducted on ont 5 the t he big tailings gs dumps dumpe of Mercur esti estimated mated to contain tons of an average value vt e of f per ton From his hia tests he learned that the 2 h per i r cent of ot cyanide solutions which whick are washed Hashed away with the tailings after the maximum extraction of values has been accomplished in the tanks imme immediately immediately immediately begins to take on new life Ufe when exposed to the air and sunlight of the lump dump and the dissolving of metal goes g goesS es I S cm em as a long l ng as the mass remains alka alkaline alkaline i 1 line with cY present to take taie ad advantage adva Sc vantage va of every stage of decomposition tion and disintegration of particles as asit asit asit it occurs These automatically dissolved dise dis val values value valS S ues uen ue Mr Crowther Crother says ys are soluble S and 81 fl simply require a k water wash to recover them in solution lution 51 and as we do donot donot dos s not have bave to avoid the destruction of i the precipitation and recovery of It precious metal becomes a simple 5 matt mattar r The avera Ver e values of ot tailings se selected selected for the tests was per Ler ton and an anve average extraction of or per pere tent e t ww wi accomplished by b merely peri per i half a ton of water through S e each fach rh ton of tailings tailing t With this show showing showing ing jag which Is 18 the equivalent of a re recovery reS S r S covery of from ton of tailings worth of gold ld Mr hEr lOwther considers it possible by this means to net at least 25 5 cents per ton 55 Tb orb gentleman gen closes his very instructive five tive and suggestive article by explain explaining explainIng ing that the capacity of each tank em era employed employed ta In such a process would be lint lim limited only by the time required to load loadS and unload and the rate of percolation S and he be believes that It If an extra pound of caustic alkali is in future added to each ton tOft of the Mercur tailings at the 5 time Urn of final washing the automatic c dissolution 4 will render soluble In water a higher hi her percentage of gold grold than the thet theS S tests t made prove to exist t as a result of J S practice practiceS H S In 1 oth other r words Mr Crowther believes 3 that the tons of tailings at atthe atthe 7 the Golden Gate and other mills in InS S Mercur can caB be handled at a profit of 38 31 cents ceu per pr ton tOft or and he be believe believes lieve that a 3 much higher extrac extraction extraction extraction tion than h hs s tests show can be very ery easily accomplished in future by allow allowing 5 ing an add pound of caustic til fl 5 Kali per ton to pass pas into the dumps S with the tailings Where There cyanide tailing dumps dompe contain greater values value than those e at Mercur he considers the problem S lent lem no chance of failure what whatever whatever ever |