g08 MINING INDUSTEY. 



is made up so as to contain not less than 30 per cent, of lead, and usually a 

 considerably higher percentage. This ^is mixed with about 10 per cent, of 

 iron and usually about 15 to 20 per cent, of lime. Each charge requires ten 

 or twelve hours' smelting. The molten lead, rich in silver, is drawn off in 

 convenient form for cupellation, while the rich slags are broken up and pre- 

 pared for resmelting. The lead, when ready for cupelling, contains, on the 

 average, about 2 per cent, of silver. The process of cupellation is performed 

 in an English furnace, and is generally like that already described in chapter 

 VI. Large buttons of fine silver are produced, sometimes weighing 600 or 

 600 pounds. The actual cost of this work could not be definitely stated. 

 The labor employed costs $4 per day and consists of the following men at 

 the Brown mill : In the dressing works, for twenty-four hours, 2 ; at the 

 roasting furnace, for twenty-four hours, 2 ; at the smelting furnace, for twenty- 

 four hours, 6 ; engineers, 2 ; sundry jobs, 1. 



The capacity of the Georgetown Smelting Works is about the same as 

 that of the Brown mill, and, when running, it employs about the same num- 

 ber of men. While in operation this establishment occasionally worked ores 

 at a stipulated price, about $100 per ton. The usual custom, however, was 

 to purchase the ores of the producer, paying at a fixed rate, according to 

 their assay value. These rates varied, on a graduated scale, from about 30 per 

 cent, of the assay value for ores containing 100 ounces of silver to the ton, 

 to 70 per cent, of the assay value for ores containing 800 ounces of silver to 

 the ton. A condition of this scale requires that the ores shall contain not less 

 than 30 per cent, of galena, and not more than 10 per cent, of gangue nor 

 more than 5 per cent, of zincblende. An excess of zinc or gangue subjected 

 the ores to corresponding deductions.' 



During the summer of 1869 this establishment had been idle for a con- 

 siderable period of time, owing, it was said, to financial embarrassments. 

 In the summer of 1868 there were worked about 90 tons of ore, producing 

 22,134 ounces of fine silver, worth about $28,500.^ Among the lots of ore 

 producing this amount were the following : 24J tons from Terrible mine, 

 yielding $510 per ton; 22 tons from Brown mine, yielding $300 per ton; 3 

 tons from Coin mine, yielding $389 33 per ton. 



^ Statement of Mr. John T. Herrick, superintendent. 



