Editing Gallium (section)

==Production and availability==
[[File:6N Gallium sealed in vacuum ampoule.jpg|thumb|left|99.9999% (6N) gallium sealed in vacuum ampoule]]
Gallium is produced exclusively as a [[by-product]] during the processing of the ores of other metals. Its main source material is [[Bauxite#Source of gallium|bauxite]], the chief ore of [[aluminium]], but minor amounts are also extracted from sulfidic zinc ores ([[sphalerite]] being the main host mineral).<ref name="Frenzel-2016a" /><ref name=FrenzelMeta-2016>{{cite journal |last1=Frenzel |first1=Max |last2=Hirsch |first2=Tamino |last3=Gutzmer |first3=Jens |title=Gallium, germanium, indium, and other trace and minor elements in sphalerite as a function of deposit type — A meta-analysis |journal=Ore Geology Reviews |date=July 2016 |volume=76 |pages=52–78 |doi=10.1016/j.oregeorev.2015.12.017 |bibcode=2016OGRv...76...52F }}</ref>  In the past, certain coals were an important source.

During the processing of [[bauxite]] to [[aluminium oxide|alumina]] in the [[Bayer process]], gallium accumulates in the [[sodium hydroxide]] liquor. From this it can be extracted by a variety of methods. The most recent is the use of [[ion-exchange resin]].<ref name="Frenzel-2016a">{{cite journal|last1=Frenzel|first1=Max|last2=Ketris|first2=Marina P.|last3=Seifert|first3=Thomas|last4=Gutzmer|first4=Jens|date=March 2016|title=On the current and future availability of gallium|journal=Resources Policy|volume=47|pages=38–50|doi=10.1016/j.resourpol.2015.11.005|bibcode=2016RePol..47...38F }}</ref> Achievable extraction efficiencies critically depend on the original concentration in the feed bauxite. At a typical feed concentration of 50&nbsp;ppm, about 15% of the contained gallium is extractable.<ref name="Frenzel-2016a" /> The remainder reports to the [[red mud]] and [[aluminium hydroxide]] streams. Gallium is removed from the ion-exchange resin in solution. Electrolysis then gives gallium metal. For [[semiconductor]] use, it is further purified with [[zone melting]] or single-crystal extraction from a melt ([[Czochralski process]]). Purities of 99.9999% are routinely achieved and commercially available.<ref name="Moskalyk">{{cite journal|last=Moskalyk|first=R. R.|date=2003|title=Gallium: the backbone of the electronics industry|journal=Minerals Engineering|volume=16|issue=10|pages=921–929|doi=10.1016/j.mineng.2003.08.003|bibcode=2003MiEng..16..921M }}</ref>

[[File:Bauxite Jamaica 1984.jpg|thumb|Bauxite mine in [[Jamaica]] (1984)]]
Its by-product status means that gallium production is constrained by the amount of bauxite, sulfidic zinc ores (and coal) extracted per year. Therefore, its availability needs to be discussed in terms of supply potential. The supply potential of a by-product is defined as that amount which is economically extractable from its host materials ''per year'' under current market conditions (i.e. technology and price).<ref>{{cite journal|last1=Frenzel|first1=M|last2=Tolosana-Delgado|first2=R|last3=Gutzmer|first3=J|date=2015|title=Assessing the supply potential of high-tech metals – A general method|journal=Resources Policy|volume=46|pages=45–58|doi=10.1016/j.resourpol.2015.08.002|bibcode=2015RePol..46...45F}}</ref> Reserves and resources are not relevant for by-products, since they ''cannot'' be extracted independently from the main-products.<ref>{{cite journal|last1=Frenzel|first1=Max|last2=Mikolajczak|first2=Claire|last3=Reuter|first3=Markus A.|last4=Gutzmer|first4=Jens|date=June 2017|title=Quantifying the relative availability of high-tech by-product metals – The cases of gallium, germanium and indium|journal=Resources Policy|volume=52|pages=327–335|doi=10.1016/j.resourpol.2017.04.008|bibcode=2017RePol..52..327F |doi-access=free}}</ref> Recent estimates put the supply potential of gallium at a minimum of 2,100&nbsp;t/yr from bauxite, 85&nbsp;t/yr from sulfidic zinc ores, and potentially 590 t/yr from coal.<ref name="Frenzel-2016a" /> These figures are significantly greater than current production (375&nbsp;t in 2016).<ref>{{cite book|url=https://minerals.usgs.gov/minerals/pubs/commodity/gallium/mcs-2017-galli.pdf |archive-url=https://web.archive.org/web/20170427232856/https://minerals.usgs.gov/minerals/pubs/commodity/gallium/mcs-2017-galli.pdf |archive-date=27 April 2017 |url-status=live|title=Gallium – In: USGS Mineral Commodity Summaries|publisher=United States Geological Survey|year=2017}}</ref> Thus, major future increases in the by-product production of gallium will be possible without significant increases in production costs or price. The average price for low-grade gallium was $120 per kilogram in 2016 and $135–140 per kilogram in 2017.<ref name="usgs2018" />

In 2017, the world's production of low-grade gallium was {{Circa|315}} tons—a decrease of 15% from 2016. China, Japan, South Korea, Russia, and Ukraine were the leading producers, while Germany ceased primary production of gallium in 2016. The yield of high-purity gallium was ca. 180 tons, mostly originating from China, Japan, Slovakia, UK and U.S. The 2017 world annual production capacity was estimated at 730 tons for low-grade and 320 tons for refined gallium.<ref name="usgs2018">[https://minerals.usgs.gov/minerals/pubs/commodity/gallium/mcs-2018-galli.pdf Galium]. USGS (2018)</ref>

China produced {{Circa|250}} tons of low-grade gallium in 2016 and {{Circa|300}} tons in 2017. It also accounted for more than half of global [[Light-emitting_diode|LED]] production.<ref name="usgs2018" /> As of July 2023, China accounted for between 80%<ref>{{Cite web |last=Kharpal |first=Arjun |date=4 July 2023 |title=What are Gallium and Germanium? China curbs exports of metals critical to chips and other tech |url=https://www.cnbc.com/2023/07/04/what-are-gallium-and-germanium-china-curbs-exports-of-metals-for-tech.html |access-date=4 July 2023 |website=CNBC |language=en}}</ref> and 95% of its production.<ref>{{Cite web |last=Lamby-Schmitt |first=Eva |title=China verhängt Ausfuhrkontrollen für seltene Metalle |url=https://www.tagesschau.de/wirtschaft/technologie/china-seltene-metalle-100.html |access-date=4 July 2023 |website=Tagesschau |language=de-DE}}</ref>