cahnite

{{Short description|Mineral}}

{{Infobox mineral

| name = Cahnite

| image = Cahnite-Rhodonite-245680.jpg

| imagesize = 260px

| alt =

| caption = Cahnite on rhodonite

| category = Borate minerals

| formula = Ca₂B[AsO₄](OH)₄

| IMAsymbol=Cah{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|doi-access=free}}

| molweight =

| strunz = 6.AC.70

| dana =

| system = Tetragonal

| class = Disphenoidal ({{overline|4}})
(same H-M symbol)

| symmetry = I{{overline|4}}

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| color = Colorless to white

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| cleavage = Perfect
On {110}

| fracture =

| tenacity = Brittle

| mohs = 3

| luster = Vitreous

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| diaphaneity = Transparent

| gravity =

| density = 3.156 g/cm³

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| references = [https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Cahnite Mineralienatlas]

}}

Cahnite (Cahnit in German, Cahnita in Spanish, Канит in Russian[http://www.mindat.org/min-851.html Mindat data sheet for Cahnite.]) is a brittle white or colorless mineral that has perfect cleavage and is usually transparent. It usually forms tetragonal-shaped crystals and it has a hardness of 3 mohs.[http://www.webmineral.com/data/Cahnite.shtml Mineral Data sheet for Cahnite.][http://www.mineralcollecting.org/data/allcategory.cgi?a=Cahnite&m=ww&ex=&a=c&c=&d=&l=&h=&v=&s=&r=&el=&pc=&elt=&pct=&elr=&pcr=&elf=&pcf=&str=&dna=&fml= Database entry from Mineral Collecting.]{{Dead link|date=July 2020 |bot=InternetArchiveBot |fix-attempted=yes }} Cahnite was discovered in the year 1921. It was named Cahnite to honor Lazard Cahn (1865–1940), who was a mineral collector and dealer. It is usually found in the Franklin Mine, in Franklin, New Jersey, but has also been found in Japan[http://sciencelinks.jp/j-east/article/200219/000020021902A0418079.php Article stating that veins of cahnite were found in Okayama Prefecture.] {{webarchive|url=https://web.archive.org/web/20120217004059/http://sciencelinks.jp/j-east/article/200219/000020021902A0418079.php |date=2012-02-17 }} as well as in the Vallerano quarries in Rome, Italy.{{Cite web |title=Cahnite |url=https://www.mindat.org/min-851.html |access-date=2022-06-26 |website=www.mindat.org}} The geological environment that it occurs in is in pegmatites cutting a changed zinc orebody.

The chemical formula for cahnite is Ca₂B[AsO₄](OH)₄.[http://database.iem.ac.ru/mincryst/s_carta.php?CAHNITE+695 Database entry for Cahnite from Mincryst.][http://www.h5.dion.ne.jp/~nspicnic/mine/database/cahnitee.htm Database entry for Cahnite from Japanese database.] It is made up of 26.91% calcium, 3.63% boron, 25.15% arsenic, 1.35% hydrogen, and 42.96% oxygen. It has a molecular weight of 297.91 grams. Cahnite is not radioactive. Cahnite is associated with these other minerals: willemite, rhodonite, pyrochroite, hedyphane, datolite, and baryte.