SMELTERS

SMELTERS. Smelting is a method of separating gold, silver, and other metals from their ores with fire and heat intense enough to melt the ores. A Spanish law of 22 August 1584 required a government smelter to be established in every mining district in the New World and required all miners to bring their gold and lead-silver to a government furnace. Ruins of crude smelters have been found in southern California. A dependence on Spanish and European knowledge of mining techniques continued in the United States throughout the nineteenth century.

In 1750 coal was first used as a fuel for smelting. Beginning in 1830, anthracite coal was used, and by 1860, smelters had nearly attained their present form. However, the era of improved metallurgical and chemical processes had scarcely begun. Colorado's gold sulfide ores defied recovery until a professor of chemistry, Nathaniel P. Hill, after conducting experiments at Swansea, Wales, and Freiberg, Germany, built the Boston and Colorado smelter at Blackhawk, Colorado, in 1867. Its successor was built at Argo (near Denver) in 1878 and managed by Richard Pearce. Pearce had collaborated with Hill on improving smelter design. The Argo facility began the smelting of copper ores in reverberatory furnaces, which radiate heat from the roof onto the treated material. A European-trained mining engineer was also responsible for the mining boom that created Leadville, Colorado. In 1877, August R. Meyer correctly determined that ores believed to be silver were in fact silver-lead carbonates. The new town was born and became a major source of silver and lead as well as a smelting center. Until 1900 the Argo smelter was the only one to smelt gold and silver ores into a crude mixture known as matte exclusively in reverberatories.

A major change in smelter design in the late 1800s was the introduction of much larger furnaces. The Black-hawk smelter had only one small calcining and one small reverberatory furnace. In 1888 Meyer Guggenheim, who had bought two mines at Leadville the year before, decided that he would make more profit if he smelted his own ores. Accordingly, he built the Philadelphia smelter at Pueblo, Colorado, with six great furnaces, each with a daily capacity of sixty tons of ore. In 1893 the largest smelters in the United States were at Denver, Pueblo, and Salt Lake City. The Washoe smelter of the Anaconda Copper Mining Company at Anaconda, Montana, had a smokestack 300 feet high with a thirty-foot inside diameter. Leading up the hillside to the base of this stack were 1,234 feet of flue 60 feet wide.

Toward the close of the nineteenth century, cutthroat competition between the smelters led to combination. On 4 April 1899 the American Smelting and Refining Company brought together eighteen of the country's largest smelting companies. In 1901 the firm of Meyer Guggenheim and his sons, the largest of the independents, joined the trust under terms that ensured them control of American Smelting.

BIBLIOGRAPHY

Fell, James E., Jr. Ores to Metal: The Rocky Mountain Smelting Industry. Lincoln: University of Nebraska Press, 1979.

Morrissey, Katherine. "Western Smelters and the Problem of Smelter Smoke." In Northwest Lands, Northwest Peoples: Readings in Environmental History. Seattle: University of Washington Press, 1999.

Spence, Clark C. Mining Engineers and the American West. New Haven, Conn.: Yale University Press, 1970.

Percy S.Fritz/f. b.