Show SEMI ORE TREATMENT IN COLORADO I 1 T I 1 I 1 I 1 by A S walter E M the mining and smelting smelling sm elting industries in colorado face a peculiar situation the ordinary lead smelting smelling sm elting practice which is the general method of extracting values in colorado at present demands certain ore reserves of which the available are being rapidly depleted direct smelting smelling sm elting of cru crude lead sulphide and lead carbonate ores are the exception rather than the rule iron ores are plentiful but the majority of these carry very little gold or silver galena conc concentrates en are available from the joplin district but the present price of lead combined with high freight and the subsequent high treatment charges make this source of lead prohibitive the lead smelters shelters sm elters naturally refuse to accept ore which they cannot smelt at a profit this latter named ore is mainly a medium grade silver highly siliceous dry ore dry meaning little or no lead content the mine owner cannot afford to do extensive development work to furnish the ore he can ship and at the same time leave good grade ore untouched because there is no market for it milling plants have limitations one by one mines have ceased operations until now only a small tonnage is being received at the lead smelters shelters sm elters of this state mills are suggested as a panacea and some activity is noticeable along these lines the arguments advanced in favor of this treatment being to concentrate the values high enough to overcome the freight rate barrier and to make a pr product acceptable to the smelters shelters sm elters those in the mountain stats states mineral age familiar with wet concentration methods know the limits of value saving in the majority of the mills the cripple creek district has a satisfactory method in use most ores in this district yield to some pyrite concentrates are shipped direct to the lead smelters shelters sm elters I 1 large larg e bodies of good g grade copper sulphide have been S opened up in this state and an outlet for these ores would t develop more the semi blast furnace g fc T the way out of this dilemma is the semi blast furnace or copper matte maite furnace A copper matte furnace can be run very nicely with a slag running 10 per cent higher in silica than a lead furnace slag less iron is required and li can be utilized if iron is too low the copper matte furnace requires less coke on the charge as the heat hea t of corn combustion bustion of the raw sulphides sulp hides replaces it the 38 inch by inch at semi furnace is capable of treating to tons of charge in twenty four hours whereas a lead furnace is doing exceptionally well to average ave rage tons charge in twenty four hours since the cottrell precipitator has been so successful in cleaning furnaces the semi furnace stands out prominently the volatile lead and zinc can be saved and utilized electric furnace a possible factor the flags from copper matte smelting smelling sm elting as has been practiced in colorado at the independent smelter at golden colo especially yielded an exceptionally clean slag the electric furnace may become a factor in ore trea treatment ament if cheap power is available processes employing preliminary and sul phat izing roasts are being perfected electro static methods of separating zinc from complex ores has made a marked saving of this metal which heretofore was lost in the lead smelting smelling sm elting practice colorado has a brilliant future in store when the processes in use will treat the ores in sight instead of trying to find the ores to meet the process A large tonnage of ore susceptible to the semi treatment is now opened up and awaiting the stimulus it needs |