Carborundum Abrasive, Silicon Carbide
Transmitted Off Crossed Polarized Light Illumination
Carborundum is a man-made abrasive also known as silicon carbide.
Significance in the Environment:
Silicon Carbide, even at trace levels, indicates that the presence of abrasive assemblages should be investigated
in the sample. Its presence in a sample indicates the use of abrasives and not the
presence of natural minerals. It is often a low level impurity in abrasive products containing primarily
garnet, or corundum (emery). When it is found with these minerals it suggests that these two natural minerals
are present not as natural background but rather as an abrasive assemblage.
Silicon carbide has an irregular series of interference colors. The combination of these
irregular colors, very high refractive indices, and sharply angular shape is used to suggest its presence.