编辑“︁石膏”︁

{{about|一種矿物|日本歌手椎名林檎的單曲|石膏 (單曲)|[[骨科]]医疗材料|石膏 (骨科)}}
{{Infobox mineral
| name        = 石膏
| category    = [[硫酸鹽礦物]]
| boxwidth    = 
| boxbgcolor  = #5a5a6a
| image       = Gypse Caresse.jpg 
| imagesize   = 260px
| caption     = 
| formula     = {{chem2|CaSO4*2H2O}}
| IMAsymbol   = Gp<ref>{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|url=https://www.cambridge.org/core/journals/mineralogical-magazine/article/imacnmnc-approved-mineral-symbols/62311F45ED37831D78603C6E6B25EE0A|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|access-date=2022-11-26|archive-date=2021-12-13|archive-url=https://web.archive.org/web/20211213204509/https://www.cambridge.org/core/journals/mineralogical-magazine/article/imacnmnc-approved-mineral-symbols/62311F45ED37831D78603C6E6B25EE0A|dead-url=no}}</ref>
| molweight   = {{chem molar mass|Ca=1|S=1|O=6|H=4}}
| strunz      = 7.CD.40
| dana        = 29.6.3.1
| system      = [[單斜]]
| class       = 棱柱體 (2/m) <br/>[[H-M記號]]：(2/m)
| symmetry    = ''I''2/a
| unit cell   = a = 5.679(5), b = 15.202(14) <br/>c = 6.522(6)&nbsp;Å; β = 118.43°; Z&nbsp;=&nbsp;4
| color       = 無色（在透射光中）到白色；由於雜質經常染上其他色調，可能是黃色、棕褐色、藍色、粉紅色、深棕色、紅棕色或灰色
| habit       = 團塊狀，平坦狀，細長且通常為棱柱形的晶體
| twinning    = {110}很常見
| cleavage    = {010}完美，{100}清晰
| fracture    = {100}貝殼狀，[001]平行分裂
| tenacity    = 柔韌、無彈性
| mohs        = 1.5–2（定義礦物）
| luster      = 玻璃到絹絲、珍珠或蠟狀光澤
| refractive  = ''n''<sub>α</sub> = 1.519–1.521<br/> ''n''<sub>β</sub> = 1.522–1.523<br/> ''n''<sub>γ</sub> = 1.529–1.530
| opticalprop = 雙軸 (+)
| birefringence = δ = 0.010
| pleochroism = 無
| 2V          = 58°
| streak      = 白色
| gravity     = 2.31–2.33
| melt        = 
| fusibility  = 5
| diagnostic  = 
| solubility  = 熱稀HCl
| diaphaneity = 透明到半透明
| other       = 
| references  = <ref>{{cite book |editor1=Anthony, John W. |editor2=Bideaux, Richard A. |editor3=Bladh, Kenneth W. |editor4=Nichols, Monte C. |title=Handbook of Mineralogy |publisher=Mineralogical Society of America |place=Chantilly, VA, US |chapter-url=http://rruff.geo.arizona.edu/doclib/hom/gypsum.pdf |chapter=Gypsum |isbn=978-0962209703 |volume=V (Borates, Carbonates, Sulfates) |year=2003 |access-date=2022-11-26 |archive-date=2012-03-08 |archive-url=https://web.archive.org/web/20120308105903/http://rruff.geo.arizona.edu/doclib/hom/gypsum.pdf |dead-url=no }}</ref><ref>[http://www.mindat.org/min-1784.html Gypsum] {{Wayback|url=http://www.mindat.org/min-1784.html |date=20180122152617 }}. Mindat</ref><ref name=Cornelis>{{citation |first1= Cornelis |last1= Klein | first2= Cornelius S. Jr. |last2= Hurlbut |year= 1985 |title= Manual of Mineralogy |publisher= John Wiley |edition= 20th |pages= [https://archive.org/details/manualofmineralo00klei/page/352 352–353] |isbn= 978-0-471-80580-9 |url-access= registration |url= https://archive.org/details/manualofmineralo00klei/page/352 }}</ref>
| var1 = 纖維石膏|var1text = 珍珠光澤纖維團塊
| var2 = [[透石膏]]|var2text = 透明和刀片狀晶體
| var3 = [[雪花石膏]]|var3text = 質地細膩，略顯色
}}
'''石膏'''，即'''生石膏'''（{{langx|en|Gypsum}}），是一種由二水合[[硫酸鈣]]組成的軟[[硫酸鹽礦物]]，化學式為{{chem2|CaSO4*2H2O}}。<ref name=Cornelis/>它被廣泛開採並用作[[肥料]]，並作為多種形式的[[灰泥]]、[[粉筆]]和[[石膏板]]的主要成分。[[雪花石膏]]是一種細膩的白色或淺色石膏品種，已被許多文化用於雕塑，包括[[古埃及]]、[[美索不達米亞]]、[[古羅馬]]、[[拜占庭帝國]]等。 石膏也可結晶為[[透石膏]]的半透明晶體。它以[[蒸發岩]]礦物和[[硬石膏]]的水合產物形式形成。

基於劃痕硬度比較的[[莫氏硬度]]標度將值2定義為石膏。

==物理性質==
[[File:Gypsum deformed cristal-MCG 7747-P4150901-black.jpg|thumb|left|140px|石膏晶體足夠柔軟，可以在手的壓力下彎曲。樣品在洛桑州地質博物館展出。]]
石膏具有中等水溶性（在25°C時約為2.0–2.5g/L）<ref name="Bock_1961">{{Cite journal| last = Bock| first = E.| year = 1961| title = On the solubility of anhydrous calcium sulphate and of gypsum in concentrated solutions of sodium chloride at 25&nbsp;°C, 30&nbsp;°C, 40&nbsp;°C, and 50&nbsp;°C| url = https://archive.org/details/sim_canadian-journal-of-chemistry_1961-09_39_9/page/1746| journal = Canadian Journal of Chemistry| volume = 39| issue = 9| pages = 1746–1751 | doi = 10.1139/v61-228}}</ref>，並且與大多數其他鹽相比，它表現出逆溶解度，在較高溫度下更難溶解。當石膏在空氣中加熱時，它會失去水分並首先轉化為[[燒石膏]]（半水合硫酸鈣），若進一步加熱，則轉化為[[硬石膏]]（無水硫酸鈣）。與硬石膏一樣，石膏在鹽溶液和鹽水中的溶解度也有很大程度上取決於[[NaCl]]的濃度。 <ref name="Bock_1961"/>

石膏的結構由鈣層 （Ca<sup>2+</sup>）和硫酸根層（{{chem2|SO4(2-)}}）離子緊密結合在一起。 這些層由[[结晶水]]分子層通過較弱的[[氫鍵]]鍵合，從而使晶體沿平面（在{010}平面中）完美解離。<ref name=Cornelis/><ref>{{cite journal| doi= 10.1016/S0008-8846(01)00675-5| last1= Mandal| first1= Pradip K|year=2002|pages=313|volume=32|journal=Cement and Concrete Research|last2=Mandal|first2=Tanuj K| title= Anion water in gypsum (CaSO<sub>4</sub>·2H<sub>2</sub>O) and hemihydrate (CaSO<sub>4</sub>·1/2H<sub>2</sub>O)| url= https://archive.org/details/sim_cement-and-concrete-research_2002-02_32_2/page/313|issue=2}}</ref>



==晶體品種==
{{main|透石膏}}
石膏在自然界中以扁平的形式存在，通常是[[孿晶]]，以及稱為[[透石膏]]的透明、可裂解的物質。透石膏的英文「{{lang|en|Selenite}}」以古希臘語中的[[月亮]]一詞命名。

透石膏也可能以絲狀纖維形式出現，在這種情況下，它通常被稱為纖維石膏。一種非常細膩的白色或淺色石膏被稱為[[雪花石膏]]，因各種裝飾用途而備受推崇。在乾旱地區，石膏可以以花狀形式出現，通常不透明並含有沙粒，被稱為[[沙漠玫瑰 (礦物)|沙漠玫瑰]]。它還形成了自然界中發現的一些最大的晶體，長達12米，以透石膏的形式存在。<ref>{{cite journal |first1= Juan Manuel |last1= García-Ruiz |first2= Roberto |last2= Villasuso |first3= Carlos |last3= Ayora |first4= Angels |last4= Canals |first5= Fermín |last5= Otálora |title= Formation of natural gypsum megacrystals in Naica, Mexico |journal= Geology |volume= 35 |issue= 4 |pages= 327–330 |year= 2007 |doi= 10.1130/G23393A.1 |bibcode= 2007Geo....35..327G |url= https://digital.csic.es/bitstream/10261/3439/1/garciaruiznaica.pdf |hdl= 10261/3439 |hdl-access= free |access-date= 2022-11-26 |archive-date= 2022-03-23 |archive-url= https://web.archive.org/web/20220323035410/https://digital.csic.es/bitstream/10261/3439/1/garciaruiznaica.pdf |dead-url= no }}</ref>

==發現==
石膏是一種常見的礦物，具有與[[沈積岩]]相關的厚而廣的[[蒸發岩]]床。石膏從湖水和海水中沉積，也從[[溫泉]]、[[火山]]蒸汽和[[礦脈]]中的硫酸鹽溶液中沉積。礦脈中的[[熱液]]硬石膏通常在近地表暴露處被地下水水合成石膏。它通常與礦物[[岩鹽]]和[[硫]]有關。石膏是最常見的硫酸鹽礦物。<ref name="DHZ1966">{{cite book |title=An Introduction to the Rock Forming Minerals | publisher=Longman |last1=Deer |first1=W.A. |last2=Howie |first2=R.A. |last3=Zussman |first3=J. |year=1966 |location=London |page=469 |isbn=978-0-582-44210-8}}</ref>純石膏是白色的，但作為雜質發現的其他物質可能會給局部沉積物帶來多種顏色。

因為石膏會隨著時間的推移溶解在水中，所以石膏很少以沙子的形式出現。 然而，美國[[新墨西哥州]][[白沙國家公園]]的獨特條件造就了710平方公里的白色石膏砂，足以為美國建築業提供1000年的[[石膏板]]。<ref name='The Albuquerque Journal 1999-02-07'>{{cite news |last = Abarr|first = James|title = Sea of sand |newspaper = The Albuquerque Journal|date = 7 February 1999|url = http://www.abqjournal.com/venue/travel/tourism/heritage_whitesands.htm|access-date = 27 January 2007|url-status=dead|archive-url=https://web.archive.org/web/20060630120616/http://www.abqjournal.com:80/venue/travel/tourism/heritage_whitesands.htm|archive-date=30 June 2006}}</ref>

來自[[火星偵察軌道衛星]]（MRO）的軌道圖片表明，火星北極地區存在石膏沙丘，<ref>[http://hirise.lpl.arizona.edu/nea.php High-resolution Mars image gallery] {{Wayback|url=http://hirise.lpl.arizona.edu/nea.php |date=20221126051827 }}. University of Arizona</ref>後來由[[火星探測漫遊者]]（MER）[[機遇號]]在地面上證實。<ref>[http://www.nasa.gov/mission_pages/mer/news/mer20111207.html NASA Mars Rover Finds Mineral Vein Deposited by Water] {{Wayback|url=http://www.nasa.gov/mission_pages/mer/news/mer20111207.html |date=20170615235154 }}, NASA, 7 December 2011.</ref>

==用途==
[[File:2.-Calera. Cal i guix (26561676342).jpg|thumb|upright=1.5|石膏作品，来自[[巴伦西亚民族学博物馆]]]]
[[File:Geography of Ohio - DPLA - aaba7b3295ff6973b6fd1e23e33cde14 (page 96) (cropped2).jpg|thumb|upright=1.25|俄亥俄州北部的石膏礦床地圖，黑色方塊表示礦床的位置，來自“俄亥俄州地理”，1923年]]
石膏有多種應用：
===建造業===
*[[石膏板]]主要用作牆壁和天花板的飾面，在建築中被稱為石膏板或乾壁。石膏為這些材料提供了一定程度的耐火性，並且將玻璃纖維添加到它們的成分中以突出這種效果。石膏的導熱性很小，因此石膏板具有一定的絕緣性能。<ref name=":0">{{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=en}}</ref>
*[[石膏砌塊]]在建築施工中像混凝土塊一樣使用。
*[[石膏砂漿]]是一種古老的用於建築施工的砂漿。
*[[波特蘭水泥]]的一種成分，用於防止[[混凝土]]閃凝（過快硬化）。

===農業===
*[[肥料]]：石膏提供兩種次生植物的常量[[植物營養學|營養素]]：鈣和硫。與石灰石不同，它通常不會影響土壤的pH值。<ref name="soilsorg"/>
*其他[[土壤改良劑]]用途：石膏可降低酸性土壤中的鋁和硼毒性。它還可以改善土壤結構，提高吸水性和通氣性。<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 |access-date=2022-11-26 |archive-date=2021-09-18 |archive-url=https://web.archive.org/web/20210918082818/https://www.soils.org/news/science-news/gypsum-agricultural-product |dead-url=no }}</ref>
*古代世界的木材替代品：由於[[青銅時代]][[克里特島]]的森林砍伐，木材變得稀缺時，石膏被用於以前使用木材的地方的建築施工。<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 | access-date= 2022-11-26 | archive-date= 2017-11-08 | archive-url= https://web.archive.org/web/20171108021923/http://www.themodernantiquarian.com/site/10854/knossos.html#fieldnotes | dead-url= no }}</ref>
*土壤[[水勢]]監測：可以將石膏塊插入土壤中，測量其電阻以得出土壤水分。<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 |access-date=23 May 2022 |isbn=978-0471491033 |archive-date=2022-06-16 |archive-url=https://web.archive.org/web/20220616051818/http://www.soil.tu-bs.de/download/downloads/pubs/2005.hsa077a.Durner-Or.SoilWaterPotentialMeasurement.pdf |dead-url=no }}</ref>

===造型、雕塑和藝術===
*[[石膏板]]用於鑄造模具和建模。
*[[雪花石膏]]是一種雕刻材料，尤其是在鋼鐵出現之前的古代，其相對柔軟的特性使其更容易雕刻。<ref>{{cite journal |last1=Rapp |first1=George |title=Soft Stones and Other Carvable Materials |journal=Archaeomineralogy |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>在[[中世紀]]和[[文藝復興]]時期，它甚至比[[大理石]]更受歡迎。<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>
*在中世紀時期，[[抄寫員]]和照明師使用它作為[[石膏底料]]的成分，將其應用於發光字母，並在發光手稿中鍍金。<ref>{{cite book |last1=Brown |first1=Michelle |title=Understanding illuminated manuscripts : a guide to technical terms |date=1995 |location=Los Angeles, California |isbn=9780892362172 |pages=58}}</ref>

===飲食===
*[[豆腐]]的凝結劑，使其最終成為膳食鈣的重要來源。<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}}</ref>
*將用於[[釀造]]的水提高[[硬水|硬度]]。<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|archive-date=2015-10-16|archive-url=https://web.archive.org/web/20151016064619/http://www.howtobrew.com/section1/chapter4-2.html|dead-url=no}}</ref>
*在烘焙中用作麵團改良劑、降低粘性，以及作為膳食鈣的烘焙食品來源。<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>是礦物酵母食品的主要成分。<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=November 2014}}</ref>

===醫藥和化妝品===
*石膏可用於手術夾板。<ref>{{cite journal |last1=Austin |first1=R.T. |title=Treatment of broken legs before and after the introduction of gypsum |url=https://archive.org/details/sim_injury_1983-03_14_5/page/389 |journal=Injury |date=March 1983 |volume=14 |issue=5 |pages=389–394 |doi=10.1016/0020-1383(83)90089-X|pmid=6347885 }}</ref>
*作為牙科中的印模。<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 |url=https://archive.org/details/sim_journal-of-prosthetic-dentistry_1990-02_63_2/page/233 |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>
*生石膏用于[[中药]]就叫做石膏。甘、辛，大寒。归肺、胃经。<ref>{{cite book |title=中国药典第一部 |page=98 |edition=2020 |url=https://db.ouryao.com/yd2020/view.php?id=f7dd5fdb77}}</ref>民国[[张锡纯 (民国)|张锡纯]]喜用石膏。《[[伤寒杂病论]]》[[麻杏甘石汤]]和后来派生的[[连花清瘟]]都用石膏。

===其他===
*一些[[鋁熱劑]]混合物中氧化鐵的替代品。<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 }}</ref>
*測試表明，石膏可用於去除污染水域的[[鉛]]<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| access-date=2022-11-26| archive-date=2020-10-30| archive-url=https://web.archive.org/web/20201030075811/https://eprints.ucm.es/18174/1/1000958.pdf| dead-url=no}}</ref>或[[砷]]<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>等污染物。

==參見==
*[[雪花石膏]]
*[[磷石膏]]

==參考資料==
{{Reflist|30em}}

==外部連結==
{{Commons}}
{{wiktionary}}
*[http://webmineral.com/data/Gypsum.shtml WebMineral data] {{Wayback|url=http://webmineral.com/data/Gypsum.shtml |date=20200908213152 }}
*[https://web.archive.org/web/20070814041825/http://mineral.galleries.com/minerals/sulfates/gypsum/gypsum.htm Mineral galleries – gypsum]
*[https://www.cdc.gov/niosh/npg/npgd0308.html CDC – NIOSH Pocket Guide to Chemical Hazards] {{Wayback|url=https://www.cdc.gov/niosh/npg/npgd0308.html |date=20221126040331 }}
*{{Cite EB1911|wstitle=Gypsum|short=x}}
*{{Cite AmCyc|wstitle=Gypsum|short=x}}

{{摩氏硬度}}
{{Authority control}}

[[Category:含钙矿物]]
[[Category:硫酸鹽礦物]]
[[Category:水成岩]]
[[Category:蒸發岩]]
[[Category:單斜晶系礦物]]
[[Category:發光礦物]]
[[Category:炼金术物质]]