Osbornite
{{Short description|Nitride mineral}}
{{Infobox mineral
| name = Osbornite
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| SMILES = [Ti].[N]
| Jmol = none
| category =
| formula = TiN
| IMAsymbol = Obn
| molweight = 61.874
| strunz = 1.BC.15
| dana = 1.1.19.1
| system = isometric
| class =
| symmetry = Fm3m
| unit cell = a = 4.24173 Å Z=4 V=76.32 Å3
| colour = golden yellow
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| tenacity = brittle
| mohs = 8.5
| luster = metallic
| streak = yellow
| diaphaneity = opaque
| density = 5.24 g/mL
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| melt = 2930 °C
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Osbornite is a naturally occurring variety of titanium nitride. It was first discovered in the Bustee meteorite in the late nineteenth century.{{cite journal |url=http://adsabs.harvard.edu/full/1984LPI....15..129C |title=Nitrogen Isotopic Composition of Osbornite from the Bustee Meteorite |last1=Carr |first1=L. P. |last2=Pillinger |first2=C. T. |journal=Lunar and Planetary Science |volume=XV |pages=129–130 |bibcode=1984LPI....15..129C}} Its crystals are golden-yellow octahedrons, combined with oldhamite. It is friable and does not dissolve in acids.{{cite book|title=Principles of Meteorics|author=E.L. Krinov|date=1960|page=335|publisher=Pergamon Press}}
Osbornite is usually found only in meteorites, but osbornite of terrestrial origin has been found in one location in the continental collision zone of Tibet. Osbornite requires extraordinarily low redox potential and very high temperatures (2500–3000 K) to form.{{cite web |display-authors=etal|last1=G. Parthasarathy |title=Osbornite (TiN): Implications for an extraterrestrial origin of carbonado- diamonds |url=https://www.researchgate.net/publication/314359536_Osbornite_TiN_Implications_for_an_extraterrestrial_origin_of_carbonado-_diamonds |website=35th International Geological Congress At: Cape Town, South Africa |date=Aug 2016}}