GNPGraystar’s Calcined Alumina is aluminum oxide that has been heated at temperatures in excess of 1,050° C (1,922° F) to drive off nearly all chemically combined water. In this form, alumina has great chemical purity, extreme hardness (9 on the Mohs hardness scale, on which diamond is 10), high density, and a high melting point (slightly above 2,000° C or 3,632° F).

GNPGraystar’s Calcined Alumina is used primarily for lapping and polishing of various products including precision optics, piezo electronics, precision bearings, optical glass, semi-conductor quartz, stainless steel, Gallium Arsenide, Germanium, and more.

Available in sizes from 1 to 50 microns.