Gilt Edge Maid Mining By shaft 350 feet deep and Company. drifts on two levels; Reduction Plant. Dry-crushing cyanide plant with rolls. cyanide Lundberg, Dorr & Wil- By tunnels, 1,800 feet in Wet-crushing son. length Clinton Mining and Min- | By tunnels several thoueral Co. Dakota Mining and Milling Co. Golden Reward Consolidated Gold Mining Co. sand feet in length. By vertical shafts, up to plant; capacity, 90 tons. To custom mill. Wet-crushing cyanide mill; capacity, 120 tons. Dry-crushing cyanide mill, capacity 200 tons Hidden Fortune Gold Crosscuts and drifts...... Wet-crushing cyanide Mining Co. Horseshoe Mining Co.... mill; capacity, 250 tons. Cyanide plant destroyed by fire, 1905. Imperial Gold Mining Co. By tunnel 2,000 feet long. Dry-crushing cyanide mill; capacity, 150 tons. Monarch Gold Mining By tunnel 1,150 feet long. Ore sent to smelter. Co. Portland Mining Co. Wasp No. 2, Mining Co.. Tunnels about two miles To smelter and custom mill. Cyanide plant; capacity, 125 tons. The gold and silver production of South Dakota during the period of years 1877 to 1906 is given in Table LXII.1 Utah. It is claimed that the placer gold amounted to about $1,000,000 in 1867. The main source of the precious metals has been the lead and copper ores, the development of which began in 1870. The annual production of gold fluctuated between one-half and one million dollars up to 1890, after which year it rose from $700,000 to $1,900,000 in 1896. In 1900, it was $4,000,000; in 1902, $3,600,000; in 1904, $4,215,000; and in 1905, $4,651,200. From 1877 to 1905, inclusive, the output has been approximately $43,948,300, while the total production to and including 1905 was $46,848,300.2 The silver product for 1905 was 12,000,000 fine ounces, having a value of $7,320,000. The production beginning with 1900, for intervals of two years, up to 1904 is as follows; in 1900, $5,745,912 or 9,267,600 ounces; in 1902, $5,740,801 or 10,831,700 ounces; and in 1904, $7,240,894 or 12,484,300 ounces. Utah was third in the production of silver in 1905 being a close second with Colorado, Montana leading. Table compiled from Mineral Resources, Mineral Industry and Reports Director of Mint. 2 T. A. I. M. E., Vol. 33, p. 836, 1903. In 1905 there were 121 mines being worked in Utah, of which 7 were placers and 114 deep mines. The yield of the deep mines was 2,181,061 tons of gold and silver ore, having an average value of $5.41 per ton.1 The mines of Utah, classified by chief product in 1905, by counties, are given in Table LXIII: 2 For production of gold and silver with associated metals, see Mineral Resources, 1905, p. 306. 2U. S. G. S., Mineral Resources, 1905, p. 315. County. The following table gives the source of production of gold and silver in Utah according to kinds of ore during 1905, by counties: 1 1 The output of the Tintic district, from 1880 to 1896, inclusive, is given in Table LXV.2 1U. S. G. S., Mineral Resources, 1905, pp. 307 and 308. ? U. S. G. S., 19th Ann. Rept., Pt. 3, pp. 615 and 686, 687, 1897–98. Gold. Silver. The average proportion of gold to silver in the ores of the Tintic district is about 1 to 400, but varies considerably in different mines: in the Mammoth, 1 to 20; in the Centennial Eureka, 1 to 100; in the Eureka Hill, 1 to 250; in the Bullion-Beck, 1 to 350; and in the Gemini, 1 to 2,000. The relative metallic constituents of the ore taken from an average of 240,000 tons coming from a majority of the mines are as follows: Ounces Gold Copper 0.1356 per ton. Ounces 52.440 per ton. Pounds 11.200 per ton. Pounds 270.000 per ton. The average value of the ore is close to $40 per ton. The Centennial Eureka ores average about $80. In general ores worth $10 to $25 per ton are milling, while those worth more than $25 are smelting ores. The low-grade ores, when rich in base metals, although poor in the precious metals, often yield a better profit by smelting than by milling.1 The average assays of the Daly-West ore, for the years 1901 and 1902, are given in the following table: 2 |