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Keilite | |
---|---|
General | |
Category | Sulfides |
Formula (repeating unit) | (Fe2+,Mg)S |
IMA symbol | Ke[1] |
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.[3][4] Keilite is named after Klaus Keil (born 1934).[3]
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]