Zincochromite

Zincochromite is a mineral; formula ZnCr2O4, It is the zinc analogue of Chromite, hence the name. Discovered in 1987 in South Karelia, Russia.Physical Properties of Zoncochromite Color: Brownish Black. Diaphaniety: Translucent to Opaque Habit: Euhedral Crystals - Occurs as well-formed crystals showing good external form. Hardness: 5.8 Luster: Sub Metallic Calculated Properties of Zincochromite Electron Density: Relectron=5.02 gm/cc Note: Zincochromite =5.32 gm/cc.Fermion Index Fermion Index = 0.05395 Boson Index = 0.94605 Photoelectric: PEZincochromite = 24.45 barns/electron U=PEZincochromite x relectron= 122.61 barns/cc.Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units) Zincochromite is Not Radioactive
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General Information:
 Chemical Formula:
ZnCr2O4
 Composition:
(Molecular Weight = 233.38 gm)
Zinc 28.02 % Zn
Chromium 44.56 % Cr
Oxygen 27.42 % O 
 Empirical Formula:
ZnCr2O4
 IMA Status:
Approved IMA
Physical Properties:
 Color:
brownish black.
 Diaphaniety:
Translucent to Opaque
 Hardness:
5.8
 Luster:
Sub Metallic
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