Bog iron

Last updated
Bog ore Limonite bog iron cm02.jpg
Bog ore

Bog iron is a form of impure iron deposit that develops in bogs or swamps by the chemical or biochemical oxidation of iron carried in solution. In general, bog ores consist primarily of iron oxyhydroxides, commonly goethite (FeO(OH)).

Contents

Iron-bearing groundwater typically emerges as a spring and the iron in it forms ferric hydroxide upon encountering the oxidizing environment of the surface. Bog ore often combines goethite, magnetite, and vugs or stained quartz. Oxidation may occur through enzyme catalysis by iron bacteria. It is not clear whether the magnetite precipitates upon the first contact with oxygen, then oxidizes to ferric compounds, or whether the ferric compounds are reduced when exposed to anoxic conditions upon burial beneath the sediment surface and reoxidized upon exhumation at the surface.[ citation needed ]

Bog iron, like other hydrous iron oxides, has a specific affinity for heavy metals. [1] This affinity combined with the porous structure and high specific surface area of bog iron make it a good natural sorbent. [2] These properties combined with the fact that bog iron is cheap to obtain are incentives for its utilization in environmental protection technologies. [2]

Part of Wall with Herma--usage of bog ore in architecture Arkadia wall with hermes01.jpg
Part of Wall with Herma —usage of bog ore in architecture

Iron made from bog ore will often contain residual silicates, which can form a glassy coating that imparts some resistance to rusting.

Typical iron-bearing groundwater emerging as a spring. The iron is oxidized to ferric hydroxide upon encountering the oxidizing environment of the surface. A large number of these springs and seeps on the flood plain provide the iron for bog iron deposits. Iron bearing water in a spring.jpg
Typical iron-bearing groundwater emerging as a spring. The iron is oxidized to ferric hydroxide upon encountering the oxidizing environment of the surface. A large number of these springs and seeps on the flood plain provide the iron for bog iron deposits.

Formation

Iron is carried to bogs in low-pH, low-dissolved oxygen iron-bearing groundwater that reaches the surface through springs, along with structures of fractures, or where groundwater intersects surface flows. [3] The iron in the water is then oxidized by dissolved oxygen or, through enzyme catalysis by iron bacteria (e.g., Thiobacillus ferrooxidans and Thiobacillus thiooxidans ) that concentrate the iron as part of their life processes. [4] Presence of these bacteria can be detected by the oily film they leave on the surface of the water. [3] This change of oxidation state causes the precipitation of fine-grained iron solids near the point of groundwater discharge. [3] A variety of iron minerals, such as goethite, magnetite, hematite, schwertmannite, and amorphous iron-aluminum-sulfate-rich solids, can be formed via oxidation of ferrous iron under the acidic conditions present. [4] All photosynthesizers play dual roles as oxygen producers, and thus passive iron oxidizers, and as surfaces to which the iron can sorb or bind. [4] This causes aquatic plants to become heavily encrusted with a light-orange floc of iron oxyhydroxide near the point of oxygen gas released from the plants. [4] Factors such as local geology, parent rock mineralogy, ground-water composition, and geochemically active microbes and plants influence the formation, growth, and persistence of iron bogs. [4] Bog iron is a renewable resource; the same bog can be harvested about once each generation. [3]

Iron extraction

Europeans developed iron smelting from bog iron during the Pre-Roman Iron Age of the 5th/4th–1st centuries BCE, and most iron of the Viking Age (late first millennium CE) was smelted from bog iron. [3] Humans can process bog iron with limited technology, since it does not have to be molten to remove many impurities. [5] Due to its easy accessibility and reducibility, bog iron was commonly used for early iron production. [6] Early metallurgists identified bog-iron deposits by indicators such as withered grass, a wet environment, hygrophilous grass-dominated vegetation, and reddish-brown solutions or depositions in nearby waters. [7] They stabbed wooden or metal sticks into the ground to detect larger ore-deposits, [7] and cut and pulled back layers of peat in the bog using turf knives to extract smaller, pea-sized nodules of bog iron. [3] Early iron-production from bog ore mostly occurred in bloomery furnaces. [7] The resources necessary for production were wood for charcoal, clay for the construction of bloomery furnaces, and water for processing. [7] Iron in the ore is reduced to a spongy iron bloom that stays in the upper part of the furnace while the undesirable elements stream downwards as slag. [8] Smelting with a bloomery furnace often results in between 10 and 20 mass percent Fe being reduced to iron bloom, while the rest is transferred into the slag. [9] The bloom must then be consolidated with a hammer to make usable wrought iron. There is some archaeological evidence that lime was added to furnaces to treat silica-rich ores that were difficult to smelt by the bloomery process. [3]

Europe

The first iron smelting attempts date to the 2nd millennium BCE in the Near East. [7] The technology then spread throughout Europe in the following two millennia, reaching Poland in the 2nd century BCE. [7] Iron production reached Scandinavia around 800–500 BCE. Iron production sites in central Sweden are dated to the late Bronze Age and the innovation might have been transmitted from both the south and the east. The ore used was limonite in the form of red soil and bog ore. From 200 CE ore from limonite-deposits in lakes was used. The ore was reduced in bloomeries. There is evidence of a direct relationship between Viking settlements in northern Europe and North America and bog iron deposits. [5] Bog iron dominated the iron production of Norse populated areas, including Scandinavia and Finland, from 500 to 1300 CE. [5] Large scale production of bog iron was also established in Iceland at sites known as "iron farms". [5] Smaller scale production sites in Iceland consisted of large farmsteads and some original Icelandic settlements, but these seemed to only produce enough iron to be self-sufficient. [5] Even after improved smelting technology made mined ores viable during the Middle Ages, bog ore remained important into modern times, particularly in peasant iron production. [10] In Russia, bog ore was the principal source of iron until the 16th century, when the superior ores of the Ural Mountains became available.[ citation needed ]

North America

Pre-Columbian

Iron was produced by the Vikings on Newfoundland around 1021 CE. [11] Excavations at L'Anse aux Meadows have found considerable evidence for the processing of bog iron and the production of iron ore. [5] The settlement at L'Anse aux Meadows was situated immediately east of a sedge peat bog and 15 kg of slag was found at the site, which would have produced around 3 kg of usable iron. [5] Analysis of the slag showed that considerably more iron could have been smelted out of the ore, indicating that the workers processing the ore had not been skilled. [5] This supports the idea that iron processing knowledge was widespread and not restricted to major centers of trade and commerce. [5] Ninety-eight nail fragments were also found at the site as well as considerable evidence for woodworking which points to the iron produced at the site possibly being used only for ship repair and not tool making. [5] [12]

Colonial North America

Bog iron was widely sought in colonial North America. The earliest known iron mines in North America are the mines from St. John's, Newfoundland, reportedly in operation by Anthony Parkhurst in 1578. [13] The first mining efforts in Virginia occurred as early as 1608. In 1619 Falling Creek Ironworks was established in Chesterfield County, Virginia. It was the location of the first blast furnace facility in North America. [14] [15]

Lake Massapoag in Massachusetts was drawn down by deepening the outlet channel in a search for bog iron. [16] The Saugus Iron Works National Historic Site, on the Saugus River in Saugus, Massachusetts, operated between 1646 and 1668. The site contains a museum and several reconstructed buildings. [17] The success of the Saugus Iron Works, and the rapid depletion of the region's natural bog iron, led the owners to send prospectors into the surrounding countryside. In 1658 the company bought 1,600 acres (6.5 km2) of land which covered areas that are now Concord, Acton, and Sudbury. They set up a large production facility in Concord, Massachusetts, along the Assabet River with dams, ponds, watercourses, and hearths, but by 1694 the natural bog iron there had also been exhausted, and the land was sold for farming. [18]

In Central and Southern New Jersey, bog ore was mined and refined for the production of naturally rust-resistant tools and wrought iron rails, many of which still grace staircases in Trenton and Camden. [19] During the American Revolution, bog iron cannonballs were cast for the colonial forces.

19th century United States

Bog iron was also found on the Eastern Shore of Maryland. The remains of a commercial smelting operation near Snow Hill, Maryland, are now a state and national historic site. Known as Furnace Town, it was called the Nassawango Iron Furnace after the nearby creek. The commercial furnace ran from about 1825 to 1850.

The Shapleigh Iron Company constructed a smelter at North Shapleigh, Maine, in 1836 to exploit a small bog iron deposit in Little Ossipee Pond. The plant commenced operation in 1837, but according to an 1854 history of Shapleigh "the business [proved] unprofitable, therefore after a few years it was abandoned." [20] [21] [22]

See also

Related Research Articles

<span class="mw-page-title-main">Smelting</span> Use of heat and a reducing agent to extract metal from ore

Smelting is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product. It is a form of extractive metallurgy that is used to obtain many metals such as iron, copper, silver, tin, lead and zinc. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal behind. The reducing agent is commonly a fossil-fuel source of carbon, such as carbon monoxide from incomplete combustion of coke—or, in earlier times, of charcoal. The oxygen in the ore binds to carbon at high temperatures, as the chemical potential energy of the bonds in carbon dioxide is lower than that of the bonds in the ore.

<span class="mw-page-title-main">Limonite</span> Hydrated iron oxide mineral

Limonite is an iron ore consisting of a mixture of hydrated iron(III) oxide-hydroxides in varying composition. The generic formula is frequently written as FeO(OH)·nH2O, although this is not entirely accurate as the ratio of oxide to hydroxide can vary quite widely. Limonite is one of the three principal iron ores, the others being hematite and magnetite, and has been mined for the production of iron since at least 400 BC.

<span class="mw-page-title-main">Goethite</span> Iron(III) oxide-hydroxide named in honor to the poet Goethe

Goethite is a mineral of the diaspore group, consisting of iron(III) oxide-hydroxide, specifically the α-polymorph. It is found in soil and other low-temperature environments such as sediment. Goethite has been well known since ancient times for its use as a pigment. Evidence has been found of its use in paint pigment samples taken from the caves of Lascaux in France. It was first described in 1806 based on samples found in the Hollertszug Mine in Herdorf, Germany. The mineral was named after the German polymath and poet Johann Wolfgang von Goethe (1749–1832).

<span class="mw-page-title-main">Wrought iron</span> Iron alloy with a very low carbon content

Wrought iron is an iron alloy with a very low carbon content in contrast to that of cast iron. It is a semi-fused mass of iron with fibrous slag inclusions, which give it a wood-like "grain" that is visible when it is etched, rusted, or bent to failure. Wrought iron is tough, malleable, ductile, corrosion resistant, and easily forge welded, but is more difficult to weld electrically.

<span class="mw-page-title-main">Iron ore</span> Ore rich in iron or the element Fe

Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the form of magnetite (Fe
3
O
4
, 72.4% Fe), hematite (Fe
2
O
3
, 69.9% Fe), goethite (FeO(OH), 62.9% Fe), limonite (FeO(OH)·n(H2O), 55% Fe), or siderite (FeCO3, 48.2% Fe).

<span class="mw-page-title-main">Chalcopyrite</span> Copper iron sulfide mineral

Chalcopyrite ( KAL-kə-PY-ryte, -⁠koh-) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green-tinged black.

<span class="mw-page-title-main">Slag</span> By-product of smelting ores and used metals

The general term slag may be a by-product or co-product of smelting (pyrometallurgical) ores and recycled metals depending on the type of material being produced. Slag is mainly a mixture of metal oxides and silicon dioxide. Broadly, it can be classified as ferrous, ferroalloy or non-ferrous/base metals. Within these general categories, slags can be further categorized by their precursor and processing conditions. Slag generated from the EAF process can contain toxic metals, which can be hazardous to human and environmental health.

<span class="mw-page-title-main">Blast furnace</span> Type of furnace used for smelting to produce industrial metals

A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. Blast refers to the combustion air being supplied above atmospheric pressure.

<span class="mw-page-title-main">Copper extraction</span> Process of extracting copper from the ground

Copper extraction refers to the methods used to obtain copper from its ores. The conversion of copper ores consists of a series of physical, chemical and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors.

<span class="mw-page-title-main">Bloomery</span> Type of furnace once used widely for smelting iron from its oxides

A bloomery is a type of metallurgical furnace once used widely for smelting iron from its oxides. The bloomery was the earliest form of smelter capable of smelting iron. Bloomeries produce a porous mass of iron and slag called a bloom. The mix of slag and iron in the bloom, termed sponge iron, is usually consolidated and further forged into wrought iron. Blast furnaces, which produce pig iron, have largely superseded bloomeries.

Pyrometallurgy is a branch of extractive metallurgy. It consists of the thermal treatment of minerals and metallurgical ores and concentrates to bring about physical and chemical transformations in the materials to enable recovery of valuable metals. Pyrometallurgical treatment may produce products able to be sold such as pure metals, or intermediate compounds or alloys, suitable as feed for further processing. Examples of elements extracted by pyrometallurgical processes include the oxides of less reactive elements like iron, copper, zinc, chromium, tin, and manganese.

<span class="mw-page-title-main">Direct reduced iron</span> Iron metal made from ore without use of a blast furnace

Direct reduced iron (DRI), also called sponge iron, is produced from the direct reduction of iron ore into iron by a reducing gas which contains elemental carbon and/or hydrogen. When hydrogen is used as the reducing gas no carbon dioxide is produced. Many ores are suitable for direct reduction.

In ore deposit geology, supergene processes or enrichment are those that occur relatively near the surface as opposed to deep hypogene processes. Supergene processes include the predominance of meteoric water circulation (i.e. water derived from precipitation) with concomitant oxidation and chemical weathering. The descending meteoric waters oxidize the primary (hypogene) sulfide ore minerals and redistribute the metallic ore elements. Supergene enrichment occurs at the base of the oxidized portion of an ore deposit. Metals that have been leached from the oxidized ore are carried downward by percolating groundwater, and react with hypogene sulfides at the supergene-hypogene boundary. The reaction produces secondary sulfides with metal contents higher than those of the primary ore. This is particularly noted in copper ore deposits where the copper sulfide minerals chalcocite (Cu2S), covellite (CuS), digenite (Cu18S10), and djurleite (Cu31S16) are deposited by the descending surface waters.

<span class="mw-page-title-main">Ironsand</span> A type of sand with heavy concentrations of iron

Ironsand, also known as iron-sand or iron sand, is a type of sand with heavy concentrations of iron. It is typically dark grey or blackish in color.

<span class="mw-page-title-main">Cornwall Iron Furnace</span> Historic district in Pennsylvania, United States

Cornwall Iron Furnace is a designated National Historic Landmark that is administered by the Pennsylvania Historical and Museum Commission in Cornwall, Lebanon County, Pennsylvania in the United States. The furnace was a leading Pennsylvania iron producer from 1742 until it was shut down in 1883. The furnaces, support buildings and surrounding community have been preserved as a historical site and museum, providing a glimpse into Lebanon County's industrial past. The site is the only intact charcoal-burning iron blast furnace in its original plantation in the western hemisphere. Established by Peter Grubb in 1742, Cornwall Furnace was operated during the Revolution by his sons Curtis and Peter Jr. who were major arms providers to George Washington. Robert Coleman acquired Cornwall Furnace after the Revolution and became Pennsylvania's first millionaire. Ownership of the furnace and its surroundings was transferred to the Commonwealth of Pennsylvania in 1932.

Lateritic nickel ore deposits are surficial, weathered rinds formed on ultramafic rocks. They account for 73% of the continental world nickel resources and will be in the future the dominant source for the mining of nickel.

<span class="mw-page-title-main">Archaeometallurgical slag</span> Artefact of ancient iron production

Archaeometallurgical slag is slag discovered and studied in the context of archaeology. Slag, the byproduct of iron-working processes such as smelting or smithing, is left at the iron-working site rather than being moved away with the product. As it weathers well, it is readily available for study. The size, shape, chemical composition and microstructure of slag are determined by features of the iron-working processes used at the time of its formation.

<span class="mw-page-title-main">Iron-rich sedimentary rocks</span> Sedimentary rocks containing 15 wt.% or more iron

Iron-rich sedimentary rocks are sedimentary rocks which contain 15 wt.% or more iron. However, most sedimentary rocks contain iron in varying degrees. The majority of these rocks were deposited during specific geologic time periods: The Precambrian, the early Paleozoic, and the middle to late Mesozoic. Overall, they make up a very small portion of the total sedimentary record.

<i>Ferrier</i> of Tannerre-en-Puisaye

The ancient ferrier of Tannerre-en-Puisaye, located in the village of Tannerre-en-Puisaye in Burgundy, France, is a historic site used for mining and working of iron. The works date from the Gallic and Gallo-Roman times. It is one of two largest ferriers in France and one of the largest in Europe. Industrial exploitation of the site ceased when it was classed as French Heritage monument in 1982.

<span class="mw-page-title-main">Magnetization roasting technology</span> Method for processing iron ores

Magnetic roasting technology refers to the process of heating materials or ores under specific atmospheric conditions to induce chemical reactions. This process selectively converts weakly magnetic iron minerals such as hematite (Fe2O3), siderite (FeCO3), and limonite (Fe2O3·nH2O) into strongly magnetic magnetite (Fe3O4) or maghemite (γ-Fe2O3), while the magnetic properties of gangue minerals remain almost unchanged.

References

  1. Kaczorek, Danuta, Gerhard W. Brümmer, and Michael Sommer (2009). "Content and Binding Forms of Heavy Metals, Aluminium and Phosphorus in Bog Iron Ores from Poland". Journal of Environmental Quality. 38 (3): 1109–1119. Bibcode:2009JEnvQ..38.1109K. doi:10.2134/jeq2008.0125. PMID   19398508. Archived from the original on 2019-02-07. Retrieved 2019-02-06 via Alliance of Crop, Soil, and Environmental Science Societies Digital Library.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. 1 2 Rzepa, Grzegorz, Tomasz Bajda, and Tadeusz Ratajczak (2009). "Utilization of bog iron ores as sorbents of heavy metals". Journal of Hazardous Materials. 162 (2–3): 1007–1013. Bibcode:2009JHzM..162.1007R. doi:10.1016/j.jhazmat.2008.05.135. PMID   18614286.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. 1 2 3 4 5 6 7 Heimann, R. B., U. Kreher, I. Spazier, and G. Wetzel (2002). "Mineralogical And Chemical Investigations Of Bloomery Slags From Prehistoric (8th Century Bc To 4th Century Ad) Iron Production Sites In Upper And Lower Lusatia, Germany". Archaeometry. 43 (2): 227–252. doi:10.1111/1475-4754.00016.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  4. 1 2 3 4 5 Stanton, M. R., D. B. Yager, D. L. Fey, and W. G. Wright (2007). "Formation and Geochemical Significance of Iron Bog Deposits - Chapter 14 - Formation and Geochemical Significance of Iron Bog Deposits" (PDF). U.S. Geological Survey Professional Paper: 1096.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. 1 2 3 4 5 6 7 8 9 10 Bowles, G., R. Bowker, and N. Samsonoff (2011). "Viking expansion and the search for bog iron". Platforum. 12: 25–37.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  6. Sitschick, H., F. Ludwig, E. Wetzel, J. Luckert, T. Höding (2005). "Raseneisenerz – auch in Brandenburg ein mineralischer Rohstoff mit bedeutender wirtschaftlicher Vergangenheit" (PDF). Brandenburgische Geowissenschaftliche Beiträge. 12: 119–128. Archived from the original (PDF) on 2019-04-06. Retrieved 2019-04-06.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  7. 1 2 3 4 5 6 Thelemann, M., W. Bebermeier, P. Holzmann, and E. Lehnhardt (2017). "Bog iron ore as a resource for prehistoric iron production in Central Europe — A case study of the Widawa catchment area in eastern Silesia, Poland". Catena. 149 (1): 474–490. Bibcode:2017Caten.149..474T. doi:10.1016/j.catena.2016.04.002. Archived (PDF) from the original on 2021-09-19.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  8. Koschke, Wolfgang (2002). "Raseneisenerz und Eisenhüttenindustrie in der nördlichen Oberlausitz". Freundeskreis Stadt- und Parkmuseum Bad Muskau E.V.
  9. Sperling, Dieter (2003). Rohstoffgewinnung und Altbergbau im Förderraum Calau. Förderverein Kulturlandschaft Niederlausitz. ISBN   978-3-9808035-2-6.
  10. Maria Sjöberg and Anton Tomilov, "Iron-Making in Peasant Communities," in Iron-making Societies: Early Industrial Development in Sweden and Russia, 1600–1900, ed. Maria Ågren, 33–60 (New York: Berghahn, 1998), 33–36, 59–60; Anders Florén, Göran Rydén, Ludmila Dashkevich, D. V. Gavrilov and Sergei Ustiantsev, "'The Social Organisation of Work at Mines, Furnaces, and Forges," in Iron-making Societies: Early Industrial Development in Sweden and Russia, 1600–1900, ed. Maria Ågren, 61–138 (New York: Berghahn, 1998), 62–65.
  11. Kuitems, Margot; Wallace, Birgitta L.; Lindsay, Charles; Scifo, Andrea; Doeve, Petra; Jenkins, Kevin; Lindauer, Susanne; Erdil, Pınar; Ledger, Paul M.; Forbes, Véronique; Vermeeren, Caroline (20 October 2021). "Evidence for European presence in the Americas in AD 1021". Nature. 601 (7893): 388–391. doi:10.1038/s41586-021-03972-8. ISSN   1476-4687. PMC   8770119 . PMID   34671168. S2CID   239051036. Our result of AD 1021 for the cutting year constitutes the only secure calendar date for the presence of Europeans across the Atlantic before the voyages of Columbus. Moreover, the fact that our results, on three different trees, converge on the same year is notable and unexpected. This coincidence strongly suggests Norse activity at L'Anse aux Meadows in AD 1021. In addition, our research demonstrates the potential of the AD 993 anomaly in atmospheric 14C concentrations for pinpointing the ages of past migrations and cultural interactions.
  12. Lewis-Simpson, Shannon (2000). Vinland Revisited: The Norse World at the Turn of the First Millennium. St. John's, Newfoundland: St. John's, Newfoundland: Historic Sites Association of Newfoundland and Labrador, Inc. ISBN   0-919735-07-X.
  13. "LETTER FROM ANTHONY PARKHURST TO RICHARD HAKLUYT, Lawyer, 1578" (PDF). Archived from the original (PDF) on 2016-10-27. Retrieved 2016-10-26.
  14. Hatch, Charles E. Jr.; Gregory, Thurlow Gates (July 1962). "The First American Blast Furnace, 1619-1622: The Birth of a Mighty Industry on Falling Creek in Virginia". The Virginia Magazine of History and Biography. 70 (3). Virginia Historical Society: 259–296. JSTOR   4246864.
  15. Geist, Christopher. "The Works at Falling Creek". Colonial Williamsburg. The Colonial Williamsburg Foundation. Retrieved 25 October 2016.
  16. Diana Muir, Reflections in Bullough's Pond, University Press of New England, 2000.
  17. "Saugus Iron Works". National Park Service. National Park Service, U.S. Department of the Interior. Retrieved 25 October 2016.
  18. Wheeler, Marian H. "The Concord Iron Works". Archived from the original on 2010-10-22. Retrieved 8 March 2018. The Concord Iron Works
  19. Barry Brady. "Early Settlers Made Iron Here" (PDF). New Jersey Pinelands Commission. Retrieved 24 Apr 2018.
  20. Loring, Rev. Amasa. A History of Shapleigh, Portland, ME: Brown and Thurston, 1854. p. 39.
  21. Leonard, Edward H. A monthly field trip of the Maine Mineralogical and Geological Society. Rocks and Minerals 5(2):49 (June 1930).
  22. Weddle, Thomas K. The Iron Age of Maine, Part II: The Shapleigh Iron Company: A Foray into Industrial (geo)Archaeology in Maine Geologic Facts and Localities. Augusta, Maine: Maine Geological Survey, November 2003. https://digitalmaine.com/mgs_publications/370/ accessed 6/9/2019.