Galena

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Galena
Lead glance
Galena - Huallanca, Bologesi, Ancash, Peru.jpg
Galena with minor pyrite
General
Category Sulfide mineral, octahedral subgroup
Formula
(repeating unit)
PbS
Strunz classification 2.CD.10
Dana classification2.8.1.1
Crystal system Cubic
Crystal class Hexoctahedral (m3m)
H–M symbol: (4/m32/m)
Space group Fm3m
Unit cell a = 5.936 Å; Z = 4
Identification
ColorLead gray and silvery
Crystal habit Cubes and octahedra, blocky, tabular and sometimes skeletal crystals
Twinning Contact, penetration and lamellar
Cleavage Cubic perfect on [001], parting on [111]
Fracture Subconchoidal
Tenacity Brittle
Mohs scale hardness2.5–2.75
Luster Metallic on cleavage planes
Streak Lead gray
Diaphaneity Opaque
Specific gravity 7.2–7.6
Optical propertiesIsotropic and opaque
Fusibility 2
Other characteristicsNatural semiconductor
References [1] [2] [3]
The rock-salt crystal structure. Each atom has six nearest neighbors, with octahedral geometry. NaCl polyhedra.png
The rock-salt crystal structure. Each atom has six nearest neighbors, with octahedral geometry.

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. [4]

Contents

Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite.

Lead ore deposits

Galena with baryte and pyrite from Cerro de Pasco, Peru; 5.8 cm x 4.8 cm x 4.4 cm (2.3 in x 1.9 in x 1.7 in) Baryte-Galena-Pyrite-203072.jpg
Galena with baryte and pyrite from Cerro de Pasco, Peru; 5.8 cm × 4.8 cm × 4.4 cm (2.3 in × 1.9 in × 1.7 in)

Galena is the main ore of lead, used since ancient times, [5] since lead can be smelted from galena in an ordinary wood fire. [6] Galena typically is found in hydrothermal veins in association with sphalerite, marcasite, chalcopyrite, cerussite, anglesite, dolomite, calcite, quartz, barite, and fluorite. It is also found in association with sphalerite in low-temperature lead-zinc deposits within limestone beds. Minor amounts are found in contact metamorphic zones, in pegmatites, and disseminated in sedimentary rock. [7]

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. [8] [9] Silver-bearing galena is almost entirely of hydrothermal origin; galena in lead-zinc deposits contains little silver. [10]

A microscopic picture of Galena Galena (Microscopic image).jpg
A microscopic picture of Galena

Galena deposits are found worldwide in various environments. [3] Noted deposits include those at Freiberg in Saxony; [1] Cornwall, the Mendips in Somerset, Derbyshire, and Cumberland in England; the Madan and Rhodope Mountains in Bulgaria; the Sullivan Mine of British Columbia; Broken Hill and Mount Isa in Australia; and the ancient mines of Sardinia.

In the United States, it occurs most notably as lead-zinc ore in the Mississippi Valley type deposits of the Lead Belt in southeastern Missouri, which is the largest known deposit, [1] and in the Driftless Area of Illinois, Iowa and Wisconsin. Galena also was a major mineral of the zinc-lead mines of the tri-state district around Joplin in southwestern Missouri and the adjoining areas of Kansas and Oklahoma. [1] Galena is also an important ore mineral in the silver mining regions of Colorado, Idaho, Utah and Montana. Of the latter, the Coeur d'Alene district of northern Idaho was most prominent. [1]

Australia is 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. [11] Most galena in Australia is found in hydrothermal deposits emplaced around 1680 million years ago, which have since been heavily metamorphosed. [12]

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). [13]

Importance

Galena is the official state mineral of the U.S. states of Kansas, [14] Missouri, [15] and Wisconsin; [16] the former mining communities of Galena, Kansas, [17] [18] and Galena, Illinois, [19] take their names from deposits of this mineral.

Crystal structure

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. [20] [3]

Divalent lead (Pb) cations and sulfur (S) anions form a close-packed cubic unit cell much like the mineral halite of the halide mineral group. Zinc, cadmium, iron, copper, antimony, arsenic, bismuth and selenium also occur in variable amounts in galena. Selenium substitutes for sulfur in the structure constituting a solid solution series. The lead telluride mineral altaite has the same crystal structure as galena. [21]

Geochemistry

Within the weathering or oxidation zone galena alters to anglesite (lead sulfate) or cerussite (lead carbonate). [22] Galena exposed to acid mine drainage can be oxidized to anglesite by naturally occurring bacteria and archaea, in a process similar to bioleaching. [23]

Uses of galena

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. [24]

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. [25] Traces of galena are frequently found at the Mississippian city at Kincaid Mounds in present-day Illinois. [26] The galena used at the site originated from deposits in southeastern and central Missouri and the Upper Mississippi Valley. [25]

Galena is the primary ore of lead, and is often mined for its silver content. [8]

It can be used as a source of lead in ceramic glaze. [27]

Galena cat's whisker detector CatWhisker.jpg
Galena cat's whisker detector

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. [28]

See also

Related Research Articles

Sphalerite

Sphalerite is a sulfide mineral with the chemical formula (Zn,Fe)S and an ore of zinc. When the iron content is high, sphalerite is an opaque black variety called marmatite. German geologist Ernst Friedrich Glocker discovered sphalerite in 1847, naming it based on the Greek word sphaleros, meaning "deceiving", due to the difficulty of identifying the mineral. Sphalerite is found in association with galena, chalcopyrite, pyrite, calcite, dolomite, quartz, rhodochrosite, and fluorite. Miners have been known to refer to sphalerite as zinc blende, black-jack, and ruby blende. Sphalerite is found in a variety of deposit types, but it is primarily in sedimentary exhalative, Mississippi-Valley type, and volcanogenic massive sulfide deposits. It is used for zinc, brass, bronze, gemstones, galvanization, pharmaceuticals, and cosmetics.

Acanthite

Acanthite (IMA symbol: Aca) is a form of silver sulfide with the chemical formula Ag2S. It crystallizes in the monoclinic system and is the stable form of silver sulfide below 173 °C (343 °F). Argentite is the stable form above that temperature. As argentite cools below that temperature its cubic form is distorted to the monoclinic form of acanthite. Below 173 °C acanthite forms directly. Acanthite is the only stable form in normal air temperature.

Anglesite

Anglesite is a lead sulfate mineral with the chemical formula PbSO4. It occurs as an oxidation product of primary lead sulfide ore, galena. Anglesite occurs as prismatic orthorhombic crystals and earthy masses, and is isomorphous with barite and celestine. It contains 74% of lead by mass and therefore has a high specific gravity of 6.3. Anglesite's color is white or gray with pale yellow streaks. It may be dark gray if impure.

Cobaltite

Cobaltite is a sulfide mineral composed of cobalt, arsenic, and sulfur, CoAsS. Its impurities may contain up to 10% iron and variable amounts of nickel. Structurally, it resembles pyrite (FeS2) with one of the sulfur atoms replaced by an arsenic atom.

Tetrahedrite

Tetrahedrite is a copper antimony sulfosalt mineral with formula: (Cu,Fe)
12
Sb
4
S
13
. It is the antimony endmember of the continuous solid solution series with arsenic-bearing tennantite. Pure endmembers of the series are seldom if ever seen in nature. Of the two, the antimony rich phase is more common. Other elements also substitute in the structure, most notably iron and zinc, along with less common silver, mercury and lead. Bismuth also substitutes for the antimony site and bismuthian tetrahedrite or annivite is a recognized variety. The related, silver dominant, mineral species freibergite, although rare, is notable in that it can contain up to 18% silver.

Bournonite

Bournonite is a sulfosalt mineral species, trithioantimoniate of lead and copper with the formula PbCuSbS3.

Sedimentary exhalative deposits

Sedimentary exhalative deposits are zinc-lead deposits originally interpreted to have been formed by discharge of metal-bearing basinal fluids onto the seafloor resulting in the precipitation of mainly stratiform ore, often with thin laminations of sulphide minerals. SEDEX deposits are hosted largely by clastic rocks deposited in intracontinental rifts or failed rift basins and passive continental margins. Since these ore deposits frequently form massive sulfide lenses, they are also named sediment-hosted massive sulfide (SHMS) deposits, as opposed to volcanic-hosted massive sulfide (VHMS) deposits. The sedimentary appearance of the thin laminations led to early interpretations that the deposits formed exclusively or mainly by exhalative processes onto the seafloor, hence the term SEDEX. However, recent study of numerous deposits indicates that shallow subsurface replacement is also an important process, in several deposits the predominant one, with only local if any exhalations onto the seafloor. For this reason, some authors prefer the term "Clastic-dominated zinc-lead deposits". As used today, therefore, the term SEDEX is not to be taken to mean that hydrothermal fluids actually vented into the overlying water column, although this may have occurred in some cases

Siegenite

Siegenite is a cobalt nickel sulfide mineral with the chemical formula (Ni,Co)
3
S
4
and is a member of the thiospinel group. It occurs as opaque steel gray octahedral crystals associated with other sulfides.

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 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.

Carbonate-hosted lead-zinc ore deposits

Carbonate-hosted lead-zinc ore deposits are important and highly valuable concentrations of lead and zinc sulfide ores hosted within carbonate formations and which share a common genetic origin.

Broken Hill ore deposit

The Broken Hill Ore Deposit is located underneath Broken Hill in western New South Wales, Australia, and is the namesake for the town. It is arguably the world's richest and largest zinc-lead ore deposit.

Admiralty mining district Alaska Mining District in the United States

The Admiralty mining district is a mining area in the U.S. state of Alaska which consists of Admiralty Island. Silver and base metals are mined, with gold recovered as a by-product.

Boleite

Boleite is a complex halide mineral with formula: KPb26Ag9Cu24(OH)48Cl62. It was first described in 1891 as an oxychloride mineral. It is an isometric mineral which forms in deep-blue cubes. There are numerous minerals related to boleite, such as pseudoboleite, cumengite, and diaboleite, and these all have the same complex crystal structure. They all contain bright-blue cubic forms and are formed in altered zones of lead and copper deposits, produced during the reaction of chloride bearing solutions with primary sulfide minerals.

Mendipite Oxyhalide of lead. Rare mineral found in the Mendip Hills

Mendipite is a rare mineral that was named in 1939 for the locality where it is found, the Mendip Hills in Somerset, England. It is an oxyhalide of lead with formula Pb3Cl2O2.

Semseyite

Semseyite is a rarely occurring sulfosalt mineral and is part of the class of lead antimony sulfides. It crystallizes in the monoclinic system with the chemical composition Pb9Sb8S21. The mineral forms dark gray to black aggregates.

The Tabataud Quarry is situated in the northwestern French Massif Central. The quarry used to be mined for its granodiorite.

The le Puy Mine is an ancient lead mine in the northwestern Massif Central, France. The mine produced mainly silver-bearing galena.

Hemihedrite

Hemihedrite is a rare lead zinc chromate silicate mineral with formula Pb10Zn(CrO4)6(SiO4)2(F,OH)2. It forms a series with the copper analogue iranite.

Köttigite

Köttigite is a rare hydrated zinc arsenate which was discovered in 1849 and named by James Dwight Dana in 1850 in honour of Otto Friedrich Köttig (1824–1892), a German chemist from Schneeberg, Saxony, who made the first chemical analysis of the mineral. It has the formula Zn
3
(AsO
4
)
2
·8H2O
and it is a dimorph of metaköttigite, which means that the two minerals have the same formula, but a different structure: köttigite is monoclinic and metaköttigite is triclinic. There are several minerals with similar formulae but with other cations in place of the zinc. Iron forms parasymplesite Fe2+
3
(AsO
4
)
2
·8H2O
; cobalt forms the distinctively coloured pinkish purple mineral erythrite Co
3
(AsO
4
)
2
·8H2O
and nickel forms annabergite Ni
3
(AsO
4
)
2
·8H2O
. Köttigite forms series with all three of these minerals and they are all members of the vivianite group.

Segnitite Common iron oxide mineral

Segnitite is a lead iron(III) arsenate mineral. Segnitite was first found in the Broken Hill ore deposit in Broken Hill, New South Wales, Australia. In 1991, segnitite was approved as a new mineral. Segnitite has since been found worldwide near similar locality types where rocks are rich in zinc and lead especially. it was named for Australian mineralogist, gemologist and petrologist Edgar Ralph Segnit. The mineral was named after E. R. Segnit due to his contributions to Australian mineralogy.

References

  1. 1 2 3 4 5 Anthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W.; Nichols, Monte C., eds. (1990). "Galena". Handbook of Mineralogy (PDF). 1. Chantilly, VA: Mineralogical Society of America. ISBN   0962209708.
  2. Galena. Webmineral
  3. 1 2 3 Galena. Mindat.org
  4. Young, Courtney A.; Taylor, Patrick R.; Anderson, Corby G. (2008). Hydrometallurgy 2008: Proceedings of the Sixth International Symposium. SME. ISBN   9780873352666.
  5. Lucas, A. (May 1928). "Silver in Ancient Times". The Journal of Egyptian Archaeology. 14 (1): 313–319. doi:10.1177/030751332801400160.
  6. Winder, C. (1993b). "The history of lead — Part 3". LEAD Action News. 2 (3). ISSN   1324-6011. Archived from the original on 31 August 2007. Retrieved 12 February 2016.
  7. Klein, Cornelis; Hurlbut, Cornelius S., Jr. (1993). Manual of mineralogy : (after James D. Dana) (21st ed.). New York: Wiley. pp. 354–356. ISBN   047157452X.
  8. 1 2 Lucas 1928.
  9. Wood, J. R.; Hsu, Y-T.; Bell, C. (2021). "Sending Laurion Back to the Future: Bronze Age Silver and the Source of Confusion". Internet Archaeology. 56.9. doi:10.11141/ia.56.9.
  10. Klein & Hurlbut 1993.
  11. "Lead". Geoscience Australia. Australian Government. Retrieved 26 June 2021.
  12. 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. doi:10.2113/gsecongeo.93.8.1307.
  13. Rickwood, P. C. (1981). "The largest crystals" (PDF). American Mineralogist. 66: 885–907.
  14. "2018 Statute Chapter 73 Article 38", Official state mineral, Kansas Legislature, retrieved 2019-12-05
  15. "Office of the Secretary of State, Missouri – State Symbols". State of Missouri. Retrieved 2009-11-12.
  16. "Wisconsin State Symbols". State of Wisconsin. Archived from the original on 2010-01-12. Retrieved 2009-11-12.
  17. Kansas Place-Names, John Rydjord, University of Oklahoma Press, 1972, p. 77 ISBN   0-8061-0994-7
  18. Gannett, Henry (1905). The Origin of Certain Place Names in the United States. Govt. Print. Off. p. 133.
  19. Galena Historical Society (June 21, 2006). "History Highlights" . Retrieved April 13, 2007.
  20. Klein & Hurlbut 1993, pp. 354–355.
  21. Klein & Hurlbut 1993, pp. 354–356.
  22. Klein & Hurlbut 1993, p. 355.
  23. Da Silva, Gabriel (2004). "Kinetics and mechanism of the bacterial and ferric sulphate oxidation of galena". Hydrometallurgy. 75: 99. doi:10.1016/j.hydromet.2004.07.001.
  24. Metropolitan Museum of Art (2005). The Art of Medicine in Ancient Egypt. New York. p. 10. ISBN   1-58839-170-1.
  25. 1 2 "Lead pollution from Native Americans attributed to crushing galena for glitter paint, adornments". Indiana University–Purdue University Indianapolis. 21 October 2019. Retrieved 11 January 2020.
  26. The Glittery Legacy of Lead at a Historic Native American Site, Atlas Obscura, November 7, 2019
  27. Glaze, http://www.thepotteries.org/types/glaze.htm.
  28. Lee, Thomas H. (2007). "The (Pre-)History of the Integrated Circuit: A Random Walk" (PDF). IEEE Solid-State Circuits Newsletter. 12 (2): 16–22. doi:10.1109/N-SSC.2007.4785573. ISSN   1098-4232.[ permanent dead link ]

Further reading