As part of a study by high-resolution X-ray diffraction of chrome ores from the Great Dyke, Zimbabwe, powder data are reported for a well-crystallized ferroan magnesiochromite spinel, in which some Cr had been replaced by Al. Data were obtained by using CuKα1 radiation, with an incident beam focusing monochromator to eliminate the Kα2 component. The cell parameter is a0=8.3123(2) Å, the figures of merit are M17=383 and F17=182 (0.0055, 17) and the calculated density is 4.50(5) Mgm−3. A small amount of sample broadening was observed and this was attributed to a mean crystallite size of 259(1) nm. © 1997 International Center for Diffraction Data.
