| Keilite | |
|---|---|
| General | |
| Category | Sulfides |
| Formula | (Fe2+,Mg)S |
| IMA symbol | Ke1 |
| Strunz classification | 2/C.15-15 |
| Dana classification | 2.8.1.9 |
| Crystal system | Isometric |
| Crystal class | Hexoctahedral |
| Space group | Fm3m (No. 225) |
| Unit cell | a = 5.1717(18)Å |
| Identification | |
| Formula mass | 81.91 gm |
| Colour | Grey |
| Crystal habit | Microscopic crystals |
| Cleavage | Distinct/good |
| Tenacity | Brittle |
| Luster | Metallic |
| Diaphaneity | Opaque |
| Specific gravity | 3.958 |
| Density | 3.958 |
Keilite is an iron-magnesium sulfide mineral with the chemical formula (Fe,Mg)S) that is found in enstatite chondrites.2 Keilite is the iron-dominant analog of niningerite.34 Keilite is named after Klaus Keil (born 1934).3
Occurrences
Examples of keilite occurrences are enstatite chondrites and the Zakłodzie meteorite.4 It appears to be confined to impact-melt influenced enstatite chondrites that were quenched. There are also some meteorites interpreted as impact-melt breccias that do not contain keilite. This is explained as a deeper burial after impact, which slowed cooling and enabled retrograde reactions (diapthoresis) to take place.5
References
References
- Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- "Keilite Mineral Data". WebMineral. Retrieved 15 February 2021.
- "Keilite" (PDF). Handbook of Mineralogy. Archived from the original (PDF) on 3 March 2016. Retrieved 15 February 2021.
- Shimizu M, Yoshida H, Mandarino JA (2002). "The New Mineral Species Keilite, (Fe,Mg)S, The Iron-Dominant Analogue of Niningerite" (PDF). The Canadian Mineralogist. 40 (6): 1687–1692. Bibcode:2002CaMin..40.1687S. doi:10.2113/gscanmin.40.6.1687. S2CID 93381076.
- Keil, Klaus (30 April 2007). "Occurrence and origin of keilite, (Fe>0.5,Mg<0.5)S, in enstatite chondrite impact-melt rocks and impact-melt breccias". Chemie der Erde - Geochemistry. 67 (1): 37–54. Bibcode:2007ChEG...67...37K. doi:10.1016/j.chemer.2006.05.002.