Braunite from the Northern Transvaal has cell dimensions a = 9,44, c = 18.76 Å, space group D4h20I41/acd. A related manganese mineral (with 16.3% Fe2O3, 4.3% CaO and 4.4% SiO2) from the Black Rock manganese mine, northwestern Cape Province has been found to have a = 9.44, c = 37.76 Å, space group D4h20I41/acd. This is considered to be an ordered version of ordinary braunite and is provisionally called braunite-II.

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