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1000 × 0.90 = 900 lb. lead, at 3.5c. $31.50 30 × 0.95 = 28.5 oz. silver, at 50c. 14.25 Gross value, f. o. b. mines $45.75 Less freight, $10, and smelting charge, $8 18.00 Net value, f. o. b. mines $27.75

Assuming an average of 6 tons of crude ore to 1 ton of concentrate, the value per ton of crude ore would be about $4.62½, and the net profit per ton about $1.62½, which figures are increased 23.75c. for each 5c. rise in the value of silver above 50c. per ounce.

The production of the Cœur d’Alene since 1895, as reported by the mines, has been as follows:

YearLead, TonsSilver, oz.Ratio [3]189637,2502,500,00067.1189757,7773,579,42461.9189856,3393,399,52460.3189950,0062,736,87254.7190081,5354,755,87758.3190168,9533,349,53348.5190274,7394,489,54960.01903[4]100,3555,751,61357.31904[4]108,9546,247,79557.4

The number of producers in the Cœur d’Alene district is comparatively small, and many of them have recently consolidated, under the name of the Federal Mining and Smelting Company. Outside of that concern are the Bunker Hill & Sullivan, the Morning and the Hercules mines, control of which has lately been secured by the American Smelting and Refining Company.