SPI Supplies Individual Microanalysis Standard Item, Synthetics Group, Chromium Oxide

This is a reflected light micrograph of a a synthetic, polished, carbon coated chromium oxide crystal. The identifying etched label, which is a feature of our standards, is invaluable for navigating in an electron beam instrument, and in this case reminds the user that this synthetic material has two phases - minor amounts of metallic chromium mixed with the oxide. This is a good standard for high concentrations of chromium. We used to use natural chromite but it was difficult to find homogeneous crystals. Chromite is now available in our minerals collection.