Virginia Iron in the Colonial Era

early furnaces during the colonial era utilized bog iron and small deposits or iron ore east of the mountains, until richer deposits were located west of the Blue Ridge
early furnaces during the colonial era utilized bog iron and small deposits or iron ore east of the mountains, until richer deposits were located west of the Blue Ridge
Source: Atlas of the Historical Geography of the United States, Distribution and Production of Iron Ore (Plate 6b, digitized by University of Richmond)

Iron is created in stars through fusion. When lighter elements (i.e., elements with fewer protons) fuse in the core of a star, they emit energy until forming iron. Furthur fusion starting with iron requires rather than releases energy, halting the process. Smaller stars then cool to become white dwarfs, then black dwarfs that drift through the universe. The iron in such stars remains in the core, unless a collision with another body releases it.

Stars with more than 25 solar masses spew their iron outward in a massive explosion. The conversion of silicon atoms into iron occurs within about one day, after which there is no more heat released from fusion:1

The sudden stoppage of energy generation causes the core to collapse and the outer layers of the star to fall onto the core. The infalling layers collapse so fast that they "bounce" off the iron core at close to the speed of light. The rebound causes the star to explode as a supernova.

When the earth coalesced 4.6 billion years ago, the heavy iron concentrated in the core. It stayed molten from the heat of compression and radioactive decay until 1-1.5 billion years ago, when the inner core crystallized and the iron (and about 4-8% nickel) "froze." The outer core or iron, nickel, and a few lighter elements has remained molten. The outer core next to the inner core is hotter than that portion at the core–mantle boundary. That temperature differential creates currents in the outer core, and the flow of molten iron creates the earth's magnetic field.2

One-third of the earth is iron, measured by weight. Other major elements are oxygen (31%), silicon (19%), magnesium (13%), nickel (1.9%), calcium (0.9%), and aluminum (0.9%). All remaining elements compose 0.3% of the earth. The iron is not evenly distributed; it is just 5% of the crust by weight. The crust is primarily oxygen (47%) and silicon (28%).

In the early days of Earth, iron was dissolved in the oceans. When cyanobacteria began to photosynthesize and the percentage of oxygen in the atmosphere increased, the iron oxidized and sank to the bottom of the ocean to form banded iron formations. Those formations are some of the most valuable mining sites for iron ore today, but no more banded iron formations will be created. There is too much oxygen in the atmosphere.

Gas exchange between today's oxygen-rich atmosphere and the oceans will quickly precipitate dissolved iron. Oceans have such low iron concentrations now that one proposal for removing carbon from the atmosphere is to dump iron particles into the middle of the ocean. That will create a spike of algae growth that will capture carbon, then carry it to the bottom to be incorporated into sediments.3

Much of the iron was deposited in Virginia's bedrock at the end of the Taconic Orogeny. Mountains were lifted up during the collision of a chunk of continental crust with the edge of Virginia eroded away during the Ordovician Period over 400 million years ago. Near the time the mountains had been reduced to a flat peneplain, sediments were primarily quartz. That hard-to-dissolve mineral was distributed from the last high spots, creating the formation known in different places as Tuscarora, Clinch, or Massanutten sandstone.

Surprisingly, yet more material eroded in the early Silurian Period and was deposited on top of the Tuscarora/Clinch/Massanutten sandstone in scattered patches. The Clinton/Cayugan series of sedimentary formations is unusually rich in iron, presumably due to the source rocks in a former volcanic island arc.

Rivers have carried iron from Silurian sandstones and from later island arc terranes that accreted onto Virginia. Clay particles across the state are stained red with hematite (oxidized iron), creating the red color of bricks from Chincoteague to Cumberland Gap. There are limonite deposits in the Valley and Ridge physiographic province. Magnetite deposits were mined near the Blue Ridge from Lynchburg to Grayson County in southwestern Virginia.4

The Native Americans in Virginia used the ore as a pigment, but did not develop the technology to smelt iron. The European colonists who arrived in the 1600's were well aware of the potential to develop an iron industry in the English colonies.

During the Seventeenth Century, England's domestic iron industry was not sufficient to meet its needs, so England imported much iron from Sweden. At the start of the 18th Century, Sweden's neighbors joined forces in the Great Northern War. That destroyed Sweden's control over the Baltic, simultaneously ending Sweden's capacity to meet demand for iron throughout Europe.

England, which had relied upon Sweden for over 80% of its imports, needed a new source.5

The Chesapeake colonies became the replacement for Sweden. The Virginia Company hoped to produce iron in Virginia, after John Smith shipped several barrels of high-quality ore from Virginia in 1608. In 1619, the company shipped 150 workers with expertise in manufacturing iron to Virginia, and another 20 ironworkers were sent in 1621.

In that year an iron furnace was constructed at Falling Creek, using funds intended for the new college at Henricus. Investing the funds in the manufacture of pig iron was expected to generate a steady set of profits. However, in the 1622 uprising led by Opechancanough nearly all of the colonists at Falling Creek were killed and the furnace never operated again. The colony depended upon European imports for a century, and then the iron production infrastructure had to be built almost from scratch.6

Small scale bloomeries smelted iron ore, including easy-to-extract bog iron. Bloomeries could produce small batches of low-carbon iron. "Blooms" of iron could be remelted and used to produce cast iron products, or reworked to incorporate more carbon and become wrought iron. Wrought iron, consisting of a mixture of iron and iron silicates, creating a fibrous product that was more malleable. It could be hammered and shaped to create tools, hinges, rims for wheels, and other products which Virginia colonists needed before the next ship arrived from England with manufactured goods for sale.

The first limonite mining was around 1760; the ore was processed in a bloomery near the Shenandsoah River. Like all colonial-era iron production, the bloomery was fueld by charcoal.

There are limonite deposits in Pulaski and Smyth counties. In the shallow residual "mountain ore" deposits there, iron was orinially combined with sulfur to form pyrite. In groundwater, the sulfur went into solution; the iron remainded with the clay minerals.

Other limonite deposits in the Oriskany sandstone and Helderberg limestone are located in the Shenandoah Valley and near Clifton Forge. The limonite was originally in Devonian shales, deposited on top of the limestone. Iron dissolved in groundwater and was transported down to the Helderberg, where it came out of solution and created concentrations of ore. A geological report notes:7

Outcrops of Oriskany ore are most commonly found on the lower slopes of the mountains a few hundred feet above the valley bottoms where they may appear for miles along the strike of the formation. Continuous ore bodies having a fairly constant thickness of from 8 to 25 feet have been worked for one-half mile. These ore bodies have not been deformed or fractured since they were deposited.

Wrought iron could be welded together by using a flux or limestone or borax to prevent the edges of metal pieces from oxidizing during the welding process.

Throughput the 1600's, Virginia lacked full scale iron furnaces. Starting in the 1700's, furnaces were built to create low-carbon pig iron. That material had to be heated and hammered in forges to add carbon and create wrought iron, which was the basic material for manufacturing products until the development of steel.

Steel, which includes a higher percentage of carbon than wrought iron to create an iron-carbon alloy (with small grains, rather than a mixture or iron and iron silicates aligned as fibers), was not manufactured in significant quantities in North America until after the Civil War. Development of the blast furnace, using of coke for both heat and as a carbon source, facilitated the creation of modern steel.

The construction of iron furnaces in the 1700's reflected the transfer of capital and expertise across the Atlantic Ocean, and the beginnings of an industrial base in North America:8

Blast furnaces cannot exist without extensive capital, industrial organization, trade networks, and technical expertise, all of which were all but unknown in America when George I ascended the British throne in 1714.

According to mercantile theory, the English colonists in North America were supposed to supply raw products to the mother country - not to compete with industries in England or take jobs away from workers in the British Isles.

Thomas Jefferson described Virginia's iron resources as follows:9

Iron The mines of iron worked at present are Callaway's, Ross's, and Ballendine's, on the South side of James river; Old's on the North side, in Albemarle; Miller's in Augusta, and Zane's in Frederic. These two last are in the valley between the Blue ridge and North mountain. Callaway's, Ross's, Millar's, and Zane's, make about 150 tons of bar iron each, in the year. Ross's makes also about 1600 tons of pig iron annually; Ballendine's 1000; Callaway's, Millar's, and Zane's, about 600 each. Besides these, a forge of Mr. Hunter's, at Fredericksburgh, makes about 300 tons a year of bar iron, from pigs imported from Maryland; and Taylor's forge on Neapsco of Patowmac, works in the same way, but to what extent I am not informed. The indications of iron in other places are numerous, and dispersed through all the middle country. The toughness of the cast iron of Ross's and Zane's furnaces is very remarkable. Pots and other utensils, cast thinner than usual, of this iron, may be safely thrown into, or out of the waggons in which they are transported. Salt-pans made of the same, and no longer wanted for that purpose, cannot be broken up, in order to be melted again, unless previously drilled in many parts.

In the western country, we are told of iron mines between the Muskingum and Ohio; of others on Kentucky, between the Cumberland and Barren rivers, between Cumberland and Tannissee, on Reedy creek, near the Long island, and on Chesnut creek, a branch of the Great Kanhaway, near where it crosses the Carolina line. What are called the iron banks, on the Missisipi, are believed, by a good judge, to have no iron in them. In general, from what is hitherto known of that country, it seems to want iron.

John Tayloe II ran the Neabsco ironworks and, after 1755, the Occoquan ironworks in partnership with Presley Thornton. In 1755, they bought 1,800 acres in Prince William County to supply fuel (charcoal) for the Occoquan furnace, and hired John Ballendine to build it. The furnace was in blast in 1756, but the partnership with John Ballendine ended in 1763.10

by 1756, the one-year old partnership at Occoquan between John Ballendine and John Tayloe II/Presley Thornton had broken down...
by 1756, the one-year old partnership at Occoquan between John Ballendine and John Tayloe II/Presley Thornton had broken down...
Source: Maryland State Archives, Maryland Gazette (November 25, 1756)

The Neabsco and Occoquan ironworks were supplied with iron from Maryland mines. They relied upon the waterpower from the Occoquan River and Neabsco Creek, charcoal from 20,000 acres of Prince William County forests owned by John Tayloe II, and oyster shells from Freestone Point used as the "flux" to lower the temperature in the furnace at which iron would separate out from the ore.11

in 1766, John Tayloe II and Presley Thornton advertised that John Ballendine had no legal right to sell any claim to the Occoquan complex to John Semple or James Douglass
in 1766, John Tayloe II and Presley Thornton advertised that John Ballendine had no legal right to sell any claim to the Occoquan complex to John Semple or James Douglass
Source: Colonial Williamsburg, The Virginia Gazette (Purdie and Dixon, June 13, 1766)

indentured servants, convict servants, and slaves fled from the Occoquan and Neabsco ironworks
indentured servants, convict servants, and slaves fled from the Occoquan and Neabsco ironworks
Source: Maryland State Archives, Maryland Gazette (September 16, 1762)

Billy, a ship carpenter, ran away from Occoquan in 1765 with fellow slaves and a convict servant
Billy, a ship carpenter, ran away from Occoquan in 1765 with fellow slaves and a convict servant
Source: Maryland State Archives, Maryland Gazette (April 4, 1765)

Billie ran away again in 1768
Billie ran away again in 1768
Source: Colonial Williamsburg, The Virginia Gazette (Rind, February 09, 1769)

slaves, convict servants, and indentured servants fled from the Neabsco ironworks by crossing the Potomac River to Maryland, hoping to get a job on a ship leading away from Virginia
slaves, convict servants, and indentured servants fled from the Neabsco ironworks by crossing the Potomac River to Maryland, hoping to get a job on a ship leading away from Virginia
Source: Colonial Williamsburg, The Virginia Gazette (Purdie and Dixon, August 29, 1766)

one runaway from Neabsco Ironworks may have sought employment at Zane's Ironworks in Frederick County
one runaway from Neabsco Ironworks may have sought employment at Zane's Ironworks in Frederick County
Source: Colonial Williamsburg, The Virginia Gazette (Purdie and Dixon, July 8, 1773)

one runaway from Neabsco Ironworks may have fled to Gwynn's Island
one runaway from Neabsco Ironworks may have fled to Gwynn's Island
Source: Colonial Williamsburg, The Virginia Gazette (Purdie, July 12, 1776)

iron ore extraction was done by hand, even after the Civil War
iron ore extraction was done by hand, even after the Civil War
Source: "The Chesapeake & Ohio Railway Directory, Containing an Illustrated History and Description of the Road," View of Iron Ore Mines, Ferrol Furnace, VA. (p.302)

iron ore in Louisa County was mined along with pyrite in gossan deposits
iron ore in Louisa County was mined along with pyrite in gossan deposits
Source: Virginia Department of Mines, Minerals and Energy, Iron in Virginia (Plate 5)

Minerals of Viginia

Pyrite in Virginia

Links

in 1856, the Tredegar Foundry produced locomotives for Virginia railroads
in 1856, the Tredegar Foundry produced locomotives for Virginia railroads
Source: The Richmond Directory, and Business Advertiser, for 1856 (p.124)

References

1. James Schombert, "End of a Star's Life," Astronomy 122: Birth and Death of Stars, University of Oregon, http://abyss.uoregon.edu/~js/ast122/lectures/lec18.html (last checked September 13, 2021)
2. "Earth's inner core was formed 1-1.5 billion years ago," Science Daily, October 7, 2015, https://www.sciencedaily.com/releases/2015/10/151007135656.htm; "Earth's Lopsided Core? Strangeness In Our Planet's Interior," EarthSky, June 14, 2021, https://earthsky.org/earth/earths-lopside-core-iron-crystallization/; "Earth Core," Science Direct, https://www.sciencedirect.com/topics/earth-and-planetary-sciences/earth-core (last checked September 13, 2021)
3. Andrew H. Knoll, A Brief History of Earth, Custom House, 2021, pp.94-95, https://www.google.com/books/edition/A_Brief_History_of_Earth/_T7yDwAAQBAJ; "Earth's Layers: What Is Earth Made Of?," Space.com, November 14, 2017, https://www.space.com/17777-what-is-earth-made-of.html (last checked September 13, 2021)
4. Lynn S. Fichter, Steve J. Baedke, "Cross Section I - Orogenic Calm in the Central Appalachian Basin, Silurian and Early Devonian; 435 - 370 mya" in "The Geological Evolution of Virginia and the Mid-Atlantic Region," James Madison University, http://csmgeo.csm.jmu.edu/geollab/vageol/vahist/I-siledev.html (last checked September 13, 2021)
5. James R. Moulton, Peter the Great and the Russian Military Campaigns During the Final Years of the Great Northern War, 1719-1721, University Press of America, 2005, p.15, www.jwu.edu/uploadedFiles/Documents/Academics/DenHon_Fac_Moulton_Article1.pdf (last checked April 17, 2013)
6. Robert Boyd Gordon, American Iron, 1607-1900, Johns Hopkins University Press, 2001, p.55, https://www.google.com/books/edition/American_Iron_1607_1900/osSG7ceTGekC; John Leander Bishop, Edwin Troxell Freedley, Edward Young, A History of American Manufactures from 1608 to 1860, Oxford University, 1861, pp.468-469, https://www.google.com/books/edition/A_History_of_American_Manufactures_from/L2UFAAAAQAAJ (last checked September 13, 2021)
7. Edwin O. Gooch, "Iron in Virginia," Mineral Resources Circular No.1, Virginia Division of Geology, 1954, p.3, https://www.dmme.virginia.gov/commercedocs/MRC_1.pdf (last checked September 13, 2021)
8. Edward F. Heite, "The Pioneer Phase Of The Chesapeake Iron Industry: Naturalization Of A Technology," Quarterly Bulletin, Archeological Society of Virginia, Volume 38, Number 3 (September 1983), p.133, https://www.google.com/books/edition/The_Pioneer_Phase_of_the_Chesapeake_Iron/WoXmygAACAAJ (last checked September 13, 2021)
9. Thomas Jefferson, "QUERY VI A notice of the mines and other subterraneous riches; its trees, plants, fruits, &c.", Notes on the State of Virginia, http://xroads.virginia.edu/~HYPER/JEFFERSON/ch06.html (last checked April 18, 2013)
10. Laura Croghan Kamoie, Neabsco and Occoquan: The Tayloe Family Iron Plantations, 1730-1830, Prince William Historical Commission, 2003, pp.21-22
11. Laura Croghan Kamoie, Neabsco and Occoquan: The Tayloe Family Iron Plantations, 1730-1830, p.29, p.35

the Big Hill deposit in Botetourt County was brown hematite
the Big Hill deposit in Botetourt County was brown hematite
Source: Library of Congress, Topographical map showing the location of Big Hill iron lands, Botetourt Co., VA


Rocks and Ridges - The Geology of Virginia
Virginia Places