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
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