Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver.[5]
In some deposits the galena contains up to 0.5% silver, a byproduct that far surpasses the main lead ore in revenue. In these deposits significant amounts of silver occur as included silver sulfide mineral phases or as limited silver in solid solution within the galena structure. These argentiferous galenas have long been an important ore of silver.[6][9] Silver-bearing galena is almost entirely of hydrothermal origin; galena in lead-zinc deposits contains little silver.[8]
Australia is the world's leading producer of lead as of 2021, most of which is extracted as galena. Argentiferous galena was accidentally discovered at Glen Osmond in 1841, and additional deposits were discovered near Broken Hill in 1876 and at Mount Isa in 1923.[10] Most galena in Australia is found in hydrothermal deposits emplaced around 1680 million years ago, which have since been heavily metamorphosed.[11]
The largest documented crystal of galena is composite cubo-octahedra from the Great Laxey Mine, Isle of Man, measuring 25 cm × 25 cm × 25 cm (10 in × 10 in × 10 in).[12]
Galena belongs to the octahedral sulfide group of minerals that have metal ions in octahedral positions, such as the iron sulfide pyrrhotite and the nickel arsenide niccolite. The galena group is named after its most common member, with other isometric members that include manganese bearing alabandite and niningerite.[8][4]
One of the oldest uses of galena was in the eye cosmetic kohl. In Ancient Egypt, this was applied around the eyes to reduce the glare of the desert sun and to repel flies, which were a potential source of disease.[21]
In pre-Columbian North America, galena was used by indigenous peoples as an ingredient in decorative paints and cosmetics, and widely traded throughout the eastern United States.[22] Traces of galena are frequently found at the Mississippian city at Kincaid Mounds in present-day Illinois.[23] The galena used at the site originated from deposits in southeastern and central Missouri and the Upper Mississippi Valley.[22]
Galena is the primary ore of lead, and is often mined for its silver content.[6] It is used as a source of lead in ceramic glaze.[24]
Galena is a semiconductor with a small band gap of about 0.4 eV, which found use in early wireless communication systems. It was used as the crystal in crystal radio receivers, in which it was used as a point-contact diode capable of rectifying alternating current to detect the radio signals. The galena crystal was used with a sharp wire, known as a "cat's whisker" in contact with it.[25]
^ abcdeAnthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W.; Nichols, Monte C., eds. (1990). "Galena". Handbook of Mineralogy(PDF). Vol. 1. Chantilly, VA: Mineralogical Society of America. ISBN0962209708.
^Young, Courtney A.; Taylor, Patrick R.; Anderson, Corby G. (2008). Hydrometallurgy 2008: Proceedings of the Sixth International Symposium. SME. ISBN9780873352666.
^ abcdeKlein, Cornelis; Hurlbut, Cornelius S. Jr. (1993). Manual of mineralogy (after James D. Dana) (21st ed.). New York: Wiley. pp. 354–356. ISBN047157452X.
^"Lead". Geoscience Australia. Australian Government. 4 March 2018. Retrieved 26 June 2021.
^Walters, Stephen; Bailey, Andrew (1998-12-01). "Geology and mineralization of the Cannington Ag-Pb-Zn deposit; an example of Broken Hill-type mineralization in the eastern succession, Mount Isa Inlier, Australia". Economic Geology. 93 (8): 1307–1329. Bibcode:1998EcGeo..93.1307W. doi:10.2113/gsecongeo.93.8.1307.
^Metropolitan Museum of Art (2005). The Art of Medicine in Ancient Egypt. New York. p. 10. ISBN1-58839-170-1.((cite book)): CS1 maint: location missing publisher (link)
