{{Short description|Oxide mineral}} {{Infobox mineral | name = Grossite | image =Grossite.png | alt = | caption = | category = Oxide minerals | formula = CaAl<sub>4</sub>O<sub>7</sub> | IMAsymbol = Gss<ref>{{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}}</ref> | molweight = | strunz = 4.CC.15 | dana = 07.03.02.01 | system = Monoclinic | class = Prismatic (2/m) <br/><small>(same H-M symbol)</small> | symmetry = ''C2/c'' | unit cell = a = 12.94, b = 8.91 <br/>c = 5.44&nbsp;[Å]; β = 107.01°; Z&nbsp;=&nbsp;4 | color = Colorless to white | colour = | habit = Lathlike or subhedral rounded grains in polycrystalline aggregates rimmed by melilite (in meteorites) | twinning = | cleavage = | fracture = | tenacity = | mohs = | luster = Vitreous | streak = White | diaphaneity = Transparent | gravity = 2.88 | density = | polish = | opticalprop = Biaxial (+) | refractive = nα = 1.618 nβ = 1.618 nγ = 1.652 | birefringence = δ = 0.034 | pleochroism = | 2V = Measured: 15° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = <ref name=HBM/><ref name=Mindat/><ref name=Webmin/> }} '''Grossite''' is a calcium aluminium oxide mineral with formula CaAl<sub>4</sub>O<sub>7</sub>. It is a colorless to white vitreous mineral which crystallizes in the monoclinic crystal system.<ref name=Mindat>[http://www.mindat.org/min-1754.html Mindat.org]</ref><ref name=Webmin>[http://webmineral.com/data/Grossite.shtml Webmineral data]</ref>

Grossite was first described 1994 for an occurrence in the Hatrurim Formation of Israel. It was named for Shulamit Gross (1923–2012) of the Geological Survey of Israel.<ref name=HBM>[http://rruff.geo.arizona.edu/doclib/hom/grossite.pdf Handbook of Mineralogy]</ref><ref name=Webmin/>

It occurs within high temperature metamorphosed impure limestone of the Hatrurim Formation and also within calcium-aluminium rich inclusions in chondritic meteorites. Associated minerals in the Hatrurium include brownmillerite, mayenite and larnite. In meteorites it occurs with perovskite, melilite, hibonite, spinel and calcium rich pyroxene.<ref name=HBM/>

==See also== * Glossary of meteoritics ==References== {{Reflist}}

{{Meteorites}}

Category:Oxide minerals Category:Monoclinic minerals Category:Minerals in space group 15 Category:Meteorite minerals