Editing Limonite (section)

==History==
{{main|History of ferrous metallurgy}}{{See|Ochre#History}}
Limonite was one of the earliest materials used as a pigment by humans, and can be seen in Neolithic [[cave painting]]s and [[pictographs]].<ref>Wilford, John Noble (13 October 2011) [https://www.nytimes.com/2011/10/14/science/14paint.html?_r=2&hp "In African Cave, Signs of an Ancient Paint Factory"] ''The New York Times''; hardcopy published 14 October 2011 under title "African Cave, Ancient Paint Factory Pushes Human Symbolic Thought ‘Far Back’" New York edition page A-14; archived by [[WebCite]] [https://web.archive.org/web/20120103231857/http://www.nytimes.com/2011/10/14/science/14paint.html?_r=1 page 1] and [https://web.archive.org/web/20220617104805/https://www.nytimes.com/2011/10/14/science/14paint.html?_r=3&pagewanted=2 page 2] on 11 March 2012</ref>

While the first iron ore was likely [[meteoric iron]], and hematite was far easier to [[Smelting|smelt]], in Africa, where the first evidence of iron metallurgy occurs,{{dubious|date=April 2022|Ferrous metallurgy in Africa}} limonite is the most prevalent iron ore. Before smelting, as the ore was heated and the water driven off, more and more of the limonite   was converted to hematite. The ore was then pounded as it was heated above 1250&nbsp;°C,<ref>Iron oxide becomes metallic iron at roughly 1250°C, almost 300 degrees below iron's melting point of 1538°C.</ref> at which temperature the metallic iron begins sticking together and non-metallic impurities are thrown off as sparks.{{dubious|date=April 2022|Ferrous metallurgy in Africa}} Complex systems developed, notably in Tanzania, to process limonite.<ref>Schmidt, Peter and Avery, Donald H. (22 September 1978) [http://www.sciencemag.org/cgi/content/abstract/201/4361/1085 "Complex Iron Smelting and Prehistoric Culture in Tanzania"] ''Science''201(4361):&nbsp;pp.&nbsp;1085&ndash;1089</ref> Nonetheless, hematite and magnetite remained the ores of choice when smelting was by [[Bloomery|bloomeries]], and it was only with the development of [[blast furnace]]s in the 1st century BCE in China<ref>Wagner, Donald B. (1999) [http://www.staff.hum.ku.dk/dbwagner/EARFE/EARFE.html "The earliest use of iron in China"] {{webarchive|url=https://web.archive.org/web/20060718053841/http://www.staff.hum.ku.dk/dbwagner/EARFE/EARFE.html |date=2006-07-18 }} pp.&nbsp;1&ndash;9 ''In'' Young, Suzanne M. M. ''et al.'' (editors) (1999) ''Metals in Antiquity'' Archaeopress, Oxford, England, {{ISBN|978-1-84171-008-2}}</ref> and about 1150 CE in Europe,<ref>Jockenhövel, Albrecht ''et al.'' (1997) [https://www.uni-muenster.de/UrFruehGeschichte/forschen/maerkischessauerland_engl.html "Archaeological Investigations on the Beginning of Blast Furnace-Technology in Central Europe"] Abteilung für Ur- und Frühgeschichtliche Archäologie, Westfälische Wilhelms-Universität Münster; abstract published as: Jockenhövel, A. (1997) "Archaeological Investigations on the Beginning of Blast Furnace-Technology in Central Europe". In Crew, Peter and Crew, Susan (editors) (1997) ''Early Ironworking in Europe: Archaeology and Experiment: Abstracts of the International Conference at Plas Tan y Bwlch 19–25 Sept. 1997'' (Plas Tan y Bwlch Occasional Papers No 3) Snowdonia National Park Study Centre, Gwynedd, Wales,  pp. 56–58. {{OCLC|470699473}}. Archived [https://web.archive.org/web/20130224111115/http://www.uni-muenster.de/UrFruehGeschichte/forschen/maerkischessauerland_engl.html here] by [[WebCite]] on 11 March 2012</ref> that the brown iron ore of limonite could be used to best advantage.

Bog iron ore and limonite were mined in the US, but this ended with the development of advanced mining techniques.

Goldbearing limonite gossans were productively mined in the [[Shasta County, California]] mining district.<ref name="Brown" /> Similar deposits were mined near [[Rio Tinto (river)|Rio Tinto]] in [[Spain]] and [[Mount Morgan, Queensland|Mount Morgan]] in [[Australia]]. In the [[Dahlonega]] gold belt in [[Lumpkin County, Georgia]] gold was mined from limonite-rich [[laterite|lateritic]] or [[saprolite]] soil. 

As saprolite deposits have been exhausted in many mining sites, limonite has become the most prominent source of nickel for use in energy dense batteries.