Zinc-Bearing Chromite (donathite?) from Norway: A Second Look

Alan C. Moore
Mineralogisk-Geologisk Museum, Sars Gate 1, Oslo 5, Norway1
1Present address: Dept. of Geology, University of Cape Town, Rondebosch 7700, South Africa.

Summary: Electron-microprobe analyses of chromites from the Helgeland area, Norway, show that they are all low in zinc. Many chromites show physical properties identical with donathite (anisotropism; polar magnetism) but have cubic lattices. One exception, from Rødøya, shows an unusual deviation from cubic symmetry and that there may exist complex intergrowths of two different tetragonal lattices and a cubic lattice. The similarity between the chromites studied and donathite suggests that the chemistry and crystallography of that mineral may be more complex than is currently accepted.

Mineralogical Magazine; September 1977 v. 41; no. 319; p. 351-355; DOI: 10.1180/minmag.1977.041.319.06
© 1977, The Mineralogical Society
Mineralogical Society (www.minersoc.org)