{{Infobox mineral | name = Fassaite | boxwidth = | boxbgcolor = | image = Fassaïte.jpg | imagesize = 260px | alt = | caption = Fassaite from Val di Fassa | category = | formula = {{chem2|Ca(Mg,Fe,Al)(Si,Al)2O6}}
| molweight = | strunz = | dana = | system = Monoclinic | class = Prismatic (2/m) <br/><small>(same H-M symbol)</small> | symmetry = ''C2/c'' (no. 15) | unit cell = | color = light-dark green, black | colour = | habit = prismatic, short, plane | twinning = | cleavage = | fracture = | tenacity = | mohs = 6 | luster = | streak = greenish-white | diaphaneity = | gravity = 2.9-3.3 | density = | polish = | opticalprop = | refractive = | birefringence = | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = <ref>{{cite journal |last1=Dowty |first1=E. |last2=Clark |first2=J.R. |journal=American Mineralogist |volume=58 |year=1973 |pages=230–242 |title=Crystal structure refinement and optical properties of a Ti3+ fassaite from the Allende Meteorite |bibcode=1973AmMin..58..230D |url=https://pubs.geoscienceworld.org/msa/ammin/article-abstract/58/3-4_Part_1/230/542780 |access-date=30 December 2020}}</ref> }}
'''Fassaite''' is a variety of augite with a very low iron content, {{chem2|Ca(Mg,Fe,Al)(Si,Al)2O6}}.<ref name=Mindat>[http://www.mindat.org/min-11019.html Mindat]</ref> It is named after the Fassa Valley, Italy.
It is thought to be a contact mineral formed at high temperature on the interface between volcanic rocks and limestone. It is also reported in meteorites.<ref>[http://geosci.uchicago.edu/~grossman/Comparative_study_mel,_fass.pdf Simon, S. B. and L. Grossman, ''A comparative study of melilite and fassaite in Types B1 and B2 refractory inclusions,'' Geochimica et Cosmochimica Acta 70 (2006) 780–798]</ref>
== References == {{Reflist}}
* {{Cite book |first=Walter |last=Schumann |series=BLV Bestimmungsbuch |title=Mineralien aus aller Welt |edition=2 |year=1991 |isbn=3-405-14003-X |pages=223 }}
Category:Inosilicates Category:Monoclinic minerals Category:Minerals in space group 15
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