24 Colorado Gold Mines. "January, 



errgetown, and of the new mineral region of Caribou, in 

 Boulder Count}*. They are designed to treat argentiferous 

 galena only. In a combined calcining and smelting furnace 

 the galena, mixed with a suitable proportion of siliceous 

 matter, is first roasted by being moved forward from the 

 stack to near the fireplace over a hearth 60 feet long. 

 Immediately behind the bridge there is a depression, into 

 which the calcined ore is drawn, and where it is fused into 

 a pasty mass, with pyrites tailings from Central City. 

 This mass of silicate of lead, with some galena and sulphide 

 of iron, is smelted, with a small percentage of metallic iron, 

 in a cupola furnace. Separating works are being put up to 

 desilverise the lead. Although the lignite answers admirably 

 in the calciners, Pennsylvania coke at 40 dols. a ton is the 

 fuel consumed in the cupola. 



Another market for Gilpin County ore is being made in 

 Idaho, about six miles from Central City, over a steep lateral 

 mountain range, where an English company is commencing 

 the erection of furnaces in the old Whale Mill of the Spanish 

 Bar Silver Mining Company. The works are near enough 

 to Central to compete with Professor Hill for the richest of 

 the gold-bearing sulphurets of that region, which it will be 

 found necessary" to mix with the more refractory ores of 

 Idaho. At about the same distance from Idaho, but much 

 more easily reached, because upon the banks of the same 

 river, is the Empire City district, which will also furnish 

 iron and copper sulphurets ; but small smelting works, 

 owned by a Swansea, firm, are already in operation at this 

 point. 



Some of the richer argentiferous galena of Gilpin County 

 finds its way to Georgetown, where Mr. J. 0. Stewart has 

 erected and is running to good profits beautifully arranged 

 silver reduction works of the Reese River type ; but to 

 describe them would be beyond the purpose of this article. 

 The prices he pays are somewhat more favourable than 

 those of Prof. Hill: but it is worthy of note that the greater 

 satisfaction of his customers arises in great measure from 

 the accuracy with which the sample is taken, and the 

 certainty the seller feels of knowing what his ore really 

 contains. 



Present Financial Position of Mining and Milling, 

 and Proposed Alteration in the Mode of Treat- 

 ing the Ores. 



So heavy is the loss entailed on the miner by the present 

 system of milling, that Mr. Reichenecher computes that the 



