Hoelite

{{Short description|Mineral}}

{{Infobox mineral

| name = Hoelite

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| image = Hoelite, sulfur - Carolaschacht Mine, Freital, Saxony, Germany.jpg

| imagesize = 260px

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| caption = Yellow acicular crystals of hoelite (picture size: 10 mm)

| category = Organic mineral

| formula = C₁₄H₈O₂

| IMAsymbol = Hoe{{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 = 10.CA.15

| dana = 50.4.2.1

| system = Monoclinic

| class = Prismatic (2/m)
(same H-M symbol)

| symmetry = P2₁/a

| unit cell = a = 15.81 Å, b = 3.967 Å
c = 7.876 Å; β = 102.67°;
Z = 2

| color = Yellow, yellowish green

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| habit = Acicular clusters; pseudo-orthorhombic

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| cleavage = Good

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| streak = Light yellow

| diaphaneity = Semitransparent

| gravity = 1.42

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| opticalprop = Biaxial (+)

| refractive = n_α≈1.75, n_β≈1.75, n_γ≈2.0

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| references = {{cite encyclopedia|title=Hoelite|editor-last1=Anthony|editor-first1=John W.|editor-last2=Bideaux|editor-first2=Richard A.|editor-last3=Bladh|editor-first3=Kenneth W.|editor-last4=Nichols|editor-first4=Monte C.|encyclopedia=Handbook of Mineralogy|publisher=Mineralogical Society of America|location=Chantilly, VA|url=http://www.handbookofmineralogy.com/pdfs/hoelite.pdf|accessdate=12 September 2017|archive-date=4 March 2016|archive-url=https://web.archive.org/web/20160304061756/http://www.handbookofmineralogy.com/pdfs/hoelite.pdf|url-status=dead}}{{cite web|last1=Barthelmy|first1=Dave|title=Hoelite|url=https://www.mindat.org/min-1915.html|publisher=Mindat.org|accessdate=12 September 2017}}

}}

Hoelite is a mineral, discovered in 1922 at Mt. Pyramide, Spitsbergen, Norway and named after Norwegian geologist Adolf Hoel (1879–1964). Its chemical formula is C₁₄H₈O₂ (9,10-anthraquinone).

It is a very rare organic mineral which occurs in coal fire environments in association with sal ammoniac and native sulfur.