Editing Gypsum (section)

==Uses==
[[File:2.-Calera. Cal i guix (26561676342).jpg|thumb|upright=1.5|Gypsum works, [[Valencian Museum of Ethnology]]]]
[[File:Algepsar d'Alfarb. Forn primer, 1 (País Valencià).jpg|thumb|Old [[Alfarb]] kiln for making plaster as a construction material]]
[[File:KirkbyThoreGypsumPlant(SimonLedingham)May2005.jpg|thumb|upright=1.3|right|British Gypsum, [[Kirkby Thore]]]]
[[File:Geography of Ohio - DPLA - aaba7b3295ff6973b6fd1e23e33cde14 (page 96) (cropped2).jpg|thumb|upright=1.25|Map of gypsum deposits in northern Ohio, black squares indicate the location of deposits, from ''"Geography of Ohio"'', 1923]]
Gypsum is used in a wide variety of applications:

===Construction industry===
*[[Drywall|Gypsum board]]<ref>*[http://www.csinet.org/s_csi/docs/9400/9361.pdf Complimentary list of MasterFormat 2004 Edition numbers and titles] (large PDF document)</ref> is primarily used as a finish for walls and ceilings, and is known in construction as plasterboard, "sheetrock", or drywall. Gypsum provides a degree of fire-resistance to these materials, and glass fibers are added to their composition to accentuate this effect. Gypsum has negligible heat conductivity, giving its plaster some insulative properties.<ref name="Bonewitz-2008">{{Cite book |last=Bonewitz |first=Ronald |title=Rock and Gem: The Definitive Guide to Rocks, Minerals, Gems, and Fossils |publisher=DK |year=2008 |location=United States |pages=47 |language=English}}</ref>
*[[Gypsum block]]s are used like concrete blocks in construction.
*[[Gypsum mortar]] is an ancient mortar used in construction.
*A component of [[Portland cement]] used to prevent flash setting (too rapid hardening) of [[concrete]].
*A wood substitute in the ancient world: For example, when wood became scarce due to deforestation on [[Bronze Age]] [[Crete]], gypsum was employed in building construction at locations where wood was previously used.<ref>{{cite journal| first= C. Michael |last= Hogan| url= http://www.themodernantiquarian.com/site/10854/knossos.html#fieldnotes |title= Knossos fieldnotes| journal= Modern Antiquarian | year= 2007}}</ref>

===Agriculture===
*[[Fertilizer]]: In the late 18th and early 19th centuries, Nova Scotia gypsum, often referred to as plaster, was a highly sought fertilizer for wheat fields in the United States.<ref>{{cite journal |jstor=3739630|title=The Gypsum Trade of the Maritime Provinces: Its Relation to American Diplomacy and Agriculture in the Early Nineteenth Century |last1=Graham |first1=Gerald S. |journal=Agricultural History |year=1938 |volume=12 |issue=3 |pages=209–223 }}</ref> Gypsum provides two of the [[plant nutrition|secondary plant macronutrients]], calcium and sulfur. Unlike limestone, it generally does not affect soil pH.<ref name="soilsorg"/>
*[[Land reclamation|Reclamation]] of [[saline soils]], regardless of pH. When gypsum is added to sodic (saline) and [[acidic soil]], the highly [[soluble]] form of [[boron]] ([[sodium metaborate]]) is converted to the less soluble calcium metaborate. The exchangeable sodium percentage is also reduced by gypsum application.<ref>[https://books.google.com/books?id=ANCBDwAAQBAJ&dq=boron+sodium+soil&pg=PA99 Genesis and Management of Sodic (Alkali) Soils.] (2017). (n.p.): Scientific Publishers.</ref><ref>{{Cite journal |doi=10.2136/sssaj1980.03615995004400010010x |first1=J. D. |last1=Oster  |first2=H. |last2=Frenkel |year=1980 |title=The chemistry of the reclamation of sodic soils with gypsum and lime |journal=[[Soil Science Society of America Journal]] |volume=44 |issue=1 |pages=41–45 |bibcode=1980SSASJ..44...41O }}</ref> The [[Zuiderzee Works]] uses gypsum for the recovered land.<ref name="ley196110">{{Cite magazine |last=Ley |first=Willy |date=October 1961 |title=The Home-Made Land |department=For Your Information |url=https://archive.org/stream/Galaxy_v19n06_1961-08#page/n65/mode/1up |magazine=Galaxy Science Fiction |pages=92–106}}</ref>
*Other [[soil conditioner]] uses: Gypsum reduces aluminium and boron toxicity in acidic soils. It also improves soil structure, water absorption, and aeration.<ref name="soilsorg">{{cite web |title=Gypsum as an agricultural product {{!}} Soil Science Society of America |url=https://www.soils.org/news/science-news/gypsum-agricultural-product/ |website=www.soils.org}}</ref>
*Soil [[water potential]] monitoring: a gypsum block can be inserted into the soil, and its electrical resistance can be measured to derive soil moisture.<ref>{{cite encyclopedia |last1=Durner |first1=W. |last2=Or |first2=D. |year=2006 |chapter=Soil water potential measurement |title=Encyclopedia of hydrological sciences |editor-last1=Anderson |editor-first1=M.G. |publisher=John Wiley & Sons Ltd. |chapter-url=http://www.soil.tu-bs.de/download/downloads/pubs/2005.hsa077a.Durner-Or.SoilWaterPotentialMeasurement.pdf |archive-url=https://web.archive.org/web/20220616051818/http://www.soil.tu-bs.de/download/downloads/pubs/2005.hsa077a.Durner-Or.SoilWaterPotentialMeasurement.pdf |archive-date=2022-06-16 |url-status=live|access-date=23 May 2022 |isbn=978-0471491033}}</ref>

===Modeling, sculpture and art===
*[[Plaster]] for casting moulds and modeling.
*As [[alabaster]], a material for sculpture, it was used especially in the ancient world before steel was developed, when its relative softness made it much easier to carve.<ref>{{cite book |last1=Rapp |first1=George |title=Archaeomineralogy |chapter=Soft Stones and Other Carvable Materials |series=Natural Science in Archaeology |date=2009 |pages=121–142 |doi=10.1007/978-3-540-78594-1_6|isbn=978-3-540-78593-4 }}</ref> During the [[Middle Ages]] and [[Renaissance]], it was preferred even to [[marble]].<ref>{{cite journal |last1=Kloppmann |first1=W. |last2=Leroux |first2=L. |last3=Bromblet |first3=P. |last4=Le Pogam |first4=P.-Y. |last5=Cooper |first5=A. H. |last6=Worley |first6=N. |last7=Guerrot |first7=C. |last8=Montech |first8=A. T. |last9=Gallas |first9=A. M. |last10=Aillaud |first10=R. |title=Competing English, Spanish, and French alabaster trade in Europe over five centuries as evidenced by isotope fingerprinting |journal=Proceedings of the National Academy of Sciences |date=7 November 2017 |volume=114 |issue=45 |pages=11856–11860 |doi=10.1073/pnas.1707450114|pmid=29078309 |pmc=5692548 |bibcode=2017PNAS..11411856K |doi-access=free }}</ref> 
*In the medieval period, [[scribe]]s and [[Illuminated manuscript|illuminators]] used it as an ingredient in [[gesso]], which was applied to illuminated letters and gilded with gold in illuminated manuscripts.<ref>{{cite book |last1=Brown |first1=Michelle |title=Understanding illuminated manuscripts : a guide to technical terms |date=1995 |location=Los Angeles, California|publisher=Yale University Press |isbn=9780892362172 |pages=58}}</ref>

===Food and drink===
*A [[tofu]] (soy bean curd) coagulant, making it ultimately a significant source of dietary [[calcium]].<ref>{{cite book |last1=Shurtleff |first1=William |title=Tofu & soymilk production : a craft and technical manual |date=2000 |publisher=Soyfoods Center |location=Lafayette, CA |isbn=9781928914044|page=99}}</ref>
*Adding [[hard water|hardness]] to water used for [[brewing]].<ref>{{cite web|url=http://www.howtobrew.com/section1/chapter4-2.html| title= Water Chemistry Adjustment for Extract Brewing|access-date=15 December 2008|first= John |last=Palmer |publisher= HowToBrew.com}}</ref>
*Used in baking as a dough conditioner, reducing stickiness, and as a baked goods source of dietary calcium.<ref>{{cite web |url=http://www.usg.com/rc/technical-specifications/fillers/food-grade-calcium-sulfate-for-baking-industry-technical-specifications-en-IG130.pdf |work=United States Gypsum Company |title=Calcium sulphate for the baking industry |access-date=1 March 2013 |archive-url=https://web.archive.org/web/20130704125140/http://www.usg.com/rc/technical-specifications/fillers/food-grade-calcium-sulfate-for-baking-industry-technical-specifications-en-IG130.pdf |archive-date=4 July 2013 |url-status=dead }}</ref> The primary component of mineral yeast food.<ref>{{cite web |url=http://www.lesaffreyeastcorp.com/sites/default/files/products_files/Tech%20Sheet%20-%20RS%20Yeast%20Food.pdf |archive-url=https://web.archive.org/web/20131029185607/http://www.lesaffreyeastcorp.com/sites/default/files/products_files/Tech%20Sheet%20-%20RS%20Yeast%20Food.pdf|work=Lesaffre Yeast Corporation |title=Tech sheet for yeast food |access-date=1 March 2013 |url-status=dead |archive-date=2013-10-29}}</ref>
*Used in mushroom cultivation to stop grains from clumping together.

===Medicine and cosmetics===
*[[Plaster]] for surgical splints.<ref>{{cite journal |last1=Austin |first1=R.T. |title=Treatment of broken legs before and after the introduction of gypsum |journal=Injury |date=March 1983 |volume=14 |issue=5 |pages=389–394 |doi=10.1016/0020-1383(83)90089-X|pmid=6347885 }}</ref>
*Impression plasters in dentistry.<ref>{{cite journal |last1=Drennon |first1=David G. |last2=Johnson |first2=Glen H. |title=The effect of immersion disinfection of elastomeric impressions on the surface detail reproduction of improved gypsum casts |journal=The Journal of Prosthetic Dentistry |date=February 1990 |volume=63 |issue=2 |pages=233–241 |doi=10.1016/0022-3913(90)90111-O|pmid=2106026 }}</ref>

===Other===
*An alternative to iron oxide in some thermite mixes.<ref>{{cite journal |last1=Govender |first1=Desania R. |last2=Focke |first2=Walter W. |last3=Tichapondwa |first3=Shepherd M. |last4=Cloete |first4=William E. |title=Burn Rate of Calcium Sulfate Dihydrate–Aluminum Thermites |journal=ACS Applied Materials & Interfaces |date=20 June 2018 |volume=10 |issue=24 |pages=20679–20687 |doi=10.1021/acsami.8b04205|pmid=29842778 |hdl=2263/66006 |s2cid=206483977 |hdl-access=free }}</ref>
*Tests have shown that gypsum can be used to remove pollutants such as [[lead]]<ref>{{cite journal| doi=10.1016/j.apgeochem.2010.04.007| title=Interaction of gypsum with lead in aqueous solutions| journal=Applied Geochemistry| volume=25| issue=7| pages=1008| year=2010| last1=Astilleros| first1=J.M.| last2=Godelitsas| first2=A.| last3=Rodríguez-Blanco| first3=J.D.| last4=Fernández-Díaz| first4=L.| last5=Prieto| first5=M.| last6=Lagoyannis| first6=A.| last7=Harissopulos| first7=S.| bibcode=2010ApGC...25.1008A| url=https://eprints.ucm.es/18174/1/1000958.pdf |archive-url=https://web.archive.org/web/20170809180523/http://eprints.ucm.es/18174/1/1000958.pdf |archive-date=2017-08-09 |url-status=live}}</ref> or [[arsenic]]<ref>{{cite journal| doi=10.2138/am.2008.2750| title=Interaction of gypsum with As(V)-bearing aqueous solutions: Surface precipitation of guerinite, sainfeldite, and Ca<sub>2</sub>NaH(AsO<sub>4</sub>)<sub>2</sub>⋅6H<sub>2</sub>O, a synthetic arsenate| journal=American Mineralogist| volume=93| issue=5–6| pages=928| year=2008| last1=Rodriguez| first1=J. D.| last2=Jimenez| first2=A.| last3=Prieto| first3=M.| last4=Torre| first4=L.| last5=Garcia-Granda| first5=S.| bibcode=2008AmMin..93..928R| s2cid=98249784}}</ref><ref>{{cite journal| doi=10.1021/cg070222+|title=Oriented Overgrowth of Pharmacolite (CaHAsO<sub>4</sub>⋅2H2O) on Gypsum (CaSO<sub>4</sub>⋅2H<sub>2</sub>O)|author1=Rodríguez-Blanco, Juan Diego |author2=Jiménez, Amalia |author3=Prieto, Manuel  |journal=Cryst. Growth Des.|year= 2007|volume= 7 |issue=12|pages=2756–2763}}
</ref> from contaminated waters.