The Native Americans of the Upper Mississippi Valley (UMV) knew of lead deposits before the area was first visited by early French explorers in the late 1600’s. The first serious attempt to settle the area occurred in 1780 when Julien Dubuque established a trading post near the present Iowa city that bears his name. With the help of the local Indians, he discovered lead deposits, built crude furnaces, and shipped it down the Mississippi River. In 1796, he received an Indian Grant from the Governor of Louisiana for the “Mines of Spain.” When Dubuque died in 1810, the Indians destroyed his home and trading post but lead continued to make its way downriver from several places.
Lead was discovered at Buck Lead, Illinois around 1810. Illinois became a state in 1816. By 1820, lead mines were operating in several locations. The early discoveries were residual float material in fields and stream gullies. Cerrusite (lead carbonate) and galena (lead sulfide) had been left behind over time as the dolomite and limestone had weathered to form soil. The “diggings” were simply holes dug wherever there seemed to be an accumulation of the lead minerals.
In 1819, Jessie W. Shull established the first permanent settlement by a U. S. citizen in what was to become Wisconsin at the present town of Shullsburg. Here the miners’ diggings were called “badger holes.” The burrowing badger remains the mascot of the State and the University of Wisconsin. Galena, Illinois and Hazel Green, Wisconsin were settled in the early 1820’s. The army provided needed protection to the early frontier miners and other settlers until after the Black Hawk War in 1832. Because of Indian hostilities, settlement in Iowa was not permitted until 1833.
In 1807 the Federal Land Office was established to determine which lands would be made available to settlers and which would be reserved for mineral leasing. Royalties on leases ranged from one-tenth to one-sixth of the value of the lead produced, paid in either cash or lead. In 1834 the General Land Survey established Sections, Townships, and Ranges. The system of leasing small mining tracts was chaotic but continued until 1846 after which all lands were sold.
By 1830, most of the lead areas in the UMV had been discovered. The population had expanded rapidly. In 1828 the population was around 10,000 miners and settlers. In 1829, annual lead production was 6,700 tons. It reached its peak in 1847 at 27,000 tons. Iowa gained statehood in 1846 and Wisconsin in 1848. The development of the region was facilitated by good transportation. The first steamboat reached Galena in 1822. Regular service began in 1827. The railroad reached Galena in 1855, marking the end of the steamboat era.
Lead production began to decline by 1848 due to depletion of ore reserves and the exodus of many miners for the California Gold Rush. The early miners followed the surface diggings downward with conventional drilling and blasting mining methods. Ore cars were loaded by hand and either hand tramming or mules were used to transport the loaded cars to the shaft. On the surface, hand jigging was used to concentrate the galena. Initially the ore was roasted in heaps to recover the lead. Cupola furnaces were introduced in the 1820’s and Scotch Hearths around 1835. Cornish miners were instrumental in bringing much of the mining and metallurgical technology to the UMV area. The ruins of early smelting furnaces have been discovered in recent years and are being preserved.
As the mines deepened, the galena gave way to sphalerite (zinc sulfide). Unfortunately, until the late 1850’s there was no market for the zinc and zinc minerals were discarded as waste. Initial efforts to smelt zinc near the mines were unsuccessful. In the 1860’s the Matthiessen and Hegeler smelter in LaSalle, Illinois was successful in utilizing the UMV zinc ores. Initially, smithsonite (zinc carbonate) was shipped to the smelter. Much of this production was from material that had previously been discarded on dumps. In the late 1860’s, sphalerite concentrates began to be used. A zinc oxide plant was operated in Mineral Point, Wisconsin from 1882 to 1931. The New Jersey Zinc Company was the last operator of this plant.
Around 1900 steam powered gravity separation mills replaced hand jigging for ore concentration. Finely crushed ore was fed to banks of multi-cell Harz jigs. Using a pulsating action the lighter dolomite particles were separated from the heavier sphalerite and galena. The jigs could also be arranged in stages with the ore passing first through rougher jigs that produced an initial concentrate that then passed to cleaner jigs to produce a final concentrate. Concentrating tables were sometimes used to capture smaller amounts of ore minerals in the tailings. When pyrite and/or marcasite (iron sulfides) in the concentrates were high, they were roasted to enable some of the iron to be removed with magnetic separators.
In 1929, the Badger Zinc Company operated the first flotation mill at Linden, Wisconsin. Flotation made it possible to produce a cleaner concentrate and remove the pyrite and barite impurities. In 1938, the Vinegar Hill Zinc Company built a custom jig-flotation mill in Cuba City, Wisconsin to serve its own needs and those of many smaller mines.
From 1900 through World War I, zinc production boomed. Production reached a peak of 64,000 tons of zinc metal in 1917. After steep declines in zinc production during the depression following the War and during the Great Depression, output rebounded to over 32,000 tons per year during World War II. However, when wartime government premium prices were removed after the war, the UMV zinc industry continued its gradual decline. The last mine closed in 1979.
During the World War I boom, the major zinc companies were the Vinegar Hill Zinc Company, the Mineral Point Zinc Company (owned by the New Jersey Zinc Company), the Wisconsin Zinc Company (owned by the American Zinc Company), and the Frontier Zinc Company. Several smaller companies were also actively mining in the district.
After World War II, the largest mining companies were the Tri-State Zinc Company, the Calumet and Hecla Consolidated Copper Company, the Vinegar Hill Zinc Company, and the Eagle-Picher Mining and Smelting Company.
Mechanized stope (room) and pillar mining was the norm after the Second World War. Stopes were typically 25-35 feet wide and 14-18 feet high to accommodate diesel powered haulage trucks and rubber-tired loaders. Mine development utilized crawler or truck-mounted drill jumbos. In areas of thick ore, multiple lifts of ore were mined leaving stopes as high as 100 feet. Pillars of barren rock or low grade ore were left in place to support the back. Haulage drifts large enough for the mining equipment were driven between multiple orebodies. Ore from a blast was loaded into a truck and transported to a grizzly at the shaft. Rocks too large to pass through the grizzly were broken with a jack hammer. A pan conveyor fed the ore to a jaw crusher from which it passed into the skip loading pockets. The crushed ore was hoisted 200-300 feet to the surface. Other deposits were accessed through inclined haulage ramps driven from the surface.
The Calumet and Hecla operations were acquired by Eagle-Picher in 1954. Vinegar Hill was acquired by American Zinc in 1955 and continued operations until 1970. Tri-State closed its operations in 1963. The New Jersey Zinc Company began a new mine and concentrator development in 1960; however, after only a few years of operations it was closed in 1971. Confronted with a sagging base metals market and new, far more restrictive environmental regulations, Eagle-Picher closed the last of its operations (including the last operating mine in the district) in 1979.
Map of the Upper Mississippi Valley Zinc-Lead Mining District, WI/IL/IA (after Heyl, et. al., USGS, 1959).
CLICK ON IMAGES TO ENLARGE.
Northwestern Mine, Galena, IL, 1904-1913.
Early lead smelter, near Galena, IL, ca. 1850.
Zinc miners “riding the can” down the mine shaft (mine and date unknown).
Mine map of the Shullsburg Unit, Eagle-Picher Co., Shullsburg, WI (after Beck, USBM, 1964)
Mechanized mining in the final days of the UMV District. (mine and date unknown).(Unless noted, photos courtesy Mark Langenfeld)