Ch. 1: Gold and Silver in 1916

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	GOLD AND SILVER.	717

	The bulk of the gold output remains mainly from the gold mills, but in decreasing proportion. In 1916 the output from cyanidation decreased, as did the recoveries by amalgamation and chlorination, and the increase in gold was entirely from the placers and from the smelting of crude ores and concentrates. The following table shows in greater detail the ore treated and the output of gold and silver mills, by States, in 1916: Gold and silver produced at mills in 1916^a



	Figures corresponding to those in this table were collected and compiled for the entire United States by the Survey for the first time in 1911, and comparison for six years can therefore now be made. The total quantity of crude ore treated and old tailings re-treated in gold and silver mills was 11,393,838 short tons in 1916 against 11,878,287 tons in 1915, 9,849,085 tons in 1914, 9,401,856 tons in 1913, 9,677,360 tons in 1912, and 9,670,483 tons in 1911. The great bulk of the ore treated, as shown, was milled in Alaska, California, South Dakota, Nevada, and Colorado, in the order named, and here the famous mills of the Homestake, Mother Lode, Grass Valley, Treadwell, Cripple Creek, Tonopah, and Goldfield mines are especially in evidence. Large numbers of smaller mills, however, mark the wide distribution of gold mining in these regions and in many other scattered districts. The total yield of gold by amalgamation in the United States in 1916 was 964,589 fine ounces, valued at $19,939,824, against 1,084,034 ounces, valued at $22,408,971, in 1915. The output in 1916 was 413,033 ounces in California, 228,761 ounces in South Dakota, 165,273

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