Lead in Virginia

lead ore at Austinville is found within the Shady Dolomite
lead ore at Austinville is found within the Shady Dolomite
Source: Virginia Department of Energy, Geology Mineral Resources

Once colonists brought guns that needed lead bullets to Virginia, there was a market for mining lead (Pb). The first lead ore deposit to be developed was in Austinville. Mining started there in 1750, and lasted until 1981. Austinville in Wythe County was the first and last place where lead was mined commercially in Virginia. As described by Virginia Energy:1

The Austinville Mine is the oldest continuously operating mine in the United States.

Lead was also mined in Albemarle County, where the Faber Mine was discovered in 1849. During the Civil War, it produced 7,000 pounds of lead. Between 1906-1919, lead and zinc ore were extracted, with silver as a secondary product.

The Faber miners found sphalerite and galena within lenses of fluorspar (CaF2). The sphalerite and galena, minerals that included lead, had been deposited when hydrothermal fluids intruded into the sedimentary rocks of the Lynchburg Formation. The sediments were metamorphosed roughly 500 million years ago when the lavas of the Catoctin Formation reached the surface. The fluorspar/flourite could be used as a flux that removed impurities, such as sulfur, when metallic mineral ore was smelted.

The Albemarle Zinc and Lead Company reopened the Faber Mine in 1906. The vein averaged four feet wide. Three shafts were sunk to 25', 50', and 120' deep.2

Lead veins at Austinville and Faber are Mississippi Valley-type deposits. Fluids rich with dissolved lead and zinc were produced as seawater evaporated in a basin. Tectonic shifts then forced high-temperature hydrothermal fluids through limestone/dolomite formations in which the lead ore was deposited.

Unlike gold and copper deposits in Virginia, the hydrothermal fluids that concentrated lead in the Austinville and Faber deposits were not associated with magma or volcanic events. The two largest lead mining districts in Virginia are not "skarn" deposits, and were not formed when a magma body intruded into carbonaceous sedimentary rocks.

In contrast, the lead present in the Great Gossan Lead District, in Carroll and Grayson counties in Virginia and extending into North Carolina, is part of a massive sulfide deposit related to submarine volcanism. Lead is a secondary mineral found in various massive sulfide deposits, such as the Tungsten Queen Deposit in the Hamme District of Mecklenburg County and North Carolina.3

In Mississippi Valley-type deposits:4

...the ore from massive sulfide deposits typically comprises greater than 50 percent pyrite and (or) pyrrhotite, and a few percent of chalcopyrite, sphalerite, and galena. The chalcopyrite, sphalerite, and galena are recovered for their economic value, but most of the pyrite and pyrrhotite end up in waste piles.

"Skarn" deposits of lead ore has also been identified in the Chopawamsic Terrane, which accreted to Laurentia as Pangea formed. Major deposits of gold, iron, and pyrite have been mined from the metamorphosed remnants of a volcanic island arc that formed in the Iapetus Ocean around 500 million years ago. Minerals were first differentiated from magma and concentrated as lava neared the surface at the island arc. The minerals were later remobilized and distributed by hydrothermal fluids, forced into faults and fissures during orogenies as Pangea formed.

Ore removed from the Valzinco Zinc Mine in Spotsylvania County included 7.8% zinc and 3.7% lead. Shafts were driven to 300' deep. The vein was about 10 feet thick and stretched for 30 miles. Commercial mining by the Berthea Mineral Company occurred in 1909-1912. The Virginia Lead and Zinc Company operated the mine during Wrld War I in 1914-1918, and again in 1927. Panaminus reopened the Valzinco Zinc Mine during World War II. It buit a 100-ton per day mill in 1942, but mining stopped in 1945 when the end of the war reduced demand.5

Shot Tower Historic State Park

Minerals of Virginia

Mining at Austinville

Links

References

1. "Lead," Virginia Energy, https://energy.virginia.gov/geology/Lead.shtml; "The Austinville Mine," Virginia Department of Energy, https://vadmme.maps.arcgis.com/apps/Cascade/index.html?appid=af329e287d334b28b8245febb0b0691e (last checked January 5, 2024)
2. "Faber Fluorine-Fluorite Mine," Diggings, https://thediggings.com/mines/usgs10203868; "Rockhounding in Albemarle County, Virginia," Virginia Rock Shop, https://varockshop.com/rockhounding/rockhound-info/field-collecting/collecting-on-your-own-in-virginia/rockhounding-in-albemarle-county-virginia/; "Fluorite (also known as Fluorspar)," Geology.com, https://geology.com/minerals/fluorite.shtml; Wilbur A. Nelson, "Geology and Mineral Resources of Albemarle County," Bulletin No. 77, Virginia Division of Geology and Mineral Resources, 1962, pp.78-79, https://energy.virginia.gov/commercedocs/BUL_77.pdf (last checked January 5, 2024)
3. Robert R. Seal II, Nora K. Foley (editors), Progress on Geoenvironmental Models for Selected Mineral Deposit Types, U. S. Geological Survey Open-File Report 02-195, 2002, p.3, p.88, https://pubs.usgs.gov/of/2002/of02-195/; D. K. Henry; J. R. Craig; M. C. Gilbert, "Ore mineralogy of the Great Gossan Lead, Virginia," Economic Geology, May 1, 1979, https://doi.org/10.2113/gsecongeo.74.3.645; M. P. Foose, J. F. Slack, and T. Casadevall, "Textural and structural evidence for a predeformation hydrothermal origin of the Tungsten Queen Deposit, Hamme District, North Carolina," Economic Geology, July 1, 1980, https://doi.org/10.2113/gsecongeo.75.4.515 (last checked January 31, 2024)
4. David L. Leach, Ryan D. Taylor, David L. Fey, Sharon F. Diehl, Richard W. Saltus; "A deposit model for Mississippi Valley-Type lead-zinc ores," Scientific Investigations Report 2010-5070-A, US Geological Survey, 2010, https://pubs.usgs.gov/publication/sir20105070A (last checked January 28, 2024)
5. "Valzinco Zinc Mine," The Diggings, https://thediggings.com/mines/usgs10067649 (last checked January 10, 2024)


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