University of Colorado

Mineral Structure Data

Zincite Group

The zincite group is composed of monoxide minerals of zinc (zincite ZnO) and beryllium (bromellite, BeO). Both Zn and Be show strong preference for tetrahedral coordination in oxygen minerals. Both of these minerals have the hexagonal wurtzite structure with the divalentcation in tetrahedral coordination with oxygen, and each oxygen in tetrahedral coordination to four divalent cations.

The crystal structure of zincite.


Zincite group unit cells.

EndMember        Zincite        Bromellite

Formula ZnO BeO Form.Wt. 81.369 25.012 Density 5.712 3.080 Mol Volume 14.246 8.122 Z 2 2 Cryst.Sys. Hexagonal Hexagonal Cryst.Class 6mm 6mm Space Group P63mc P63mc Cell Parameters a 3.2427 2.6984 c 5.1948 4.2770 Vol. 47.306 26.970 Ref. Sabine & Sabine & Hogg(1969) Hogg (1969) Thermal Expansion(Volumetric) alpha a0 a1 a2 Elastic Properties Ks(GPa) G(Gpa)


Zincite Group Cation Sites

EndMember        Zincite        Bromellite

C.N. 4 4 Occupant Zn Be Point Sym. 3m 3m Wyckoff Not. 2b 2b Frac.Coord. x 1/3 1/3 y 2/3 2/3 z 0 0 Distances O1(1) 1.988 1.619 O2(3) 1.969 1.642 Mean 1.974 1.636 sigma .009 .011 Poly.Vol. 3.942 2.247 Q. E. 1.0006 1.0005 Ang. Var. 2.6 1.5 Site Energy 1105. 1333.


Mineral Data Base Index

GEOL 1010 Syllabus

GEOL 3010 Syllabus

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