Chromium(iii) oxide is the inorganic compound of the formula cr2o3. It is one of the principal oxides of chromium and is used as a pigment. In nature, it occurs as the rare mineral eskolaite. Properties Chemical formulacr2o3 Molar mass151.9904 g/mol Appearancelight to dark green, fine crystals Density5.22 g/cm3 Melting point2435 c Boiling point4000 c Solubility in waterinsoluble Solubility inalcoholinsoluble in alcohol, acetone, acids [applications] Because of its considerable stability, chromia is a commonly used pigment and was originally called viridian.It is used in paints, inks, and glasses. It is the colourant in "chrome green" and "institutional green." Chromium(iii) oxide is a precursor to the magnetic pigment chromium dioxide.It is one of the materials that are used when polishing (also called stropping) the edges of knives, razors