A fine abrasive for use with water and felt polishing pads or tumblers, used to speed up the polishing process.
Can be used with a hand pad for light surface clean-up, powered hand tools for scratch and surface repair, or as the final polishing step with multi-stage edging/bevelling/polishing equipment.
This is similar to the more expensive cerium oxide but gives a slightly matt finish to the glass surface.
It can also reduce the issue of fingerprint marks being left on sandblasted glasswork by 'closing the pores' of the glass surface thus eliminating the need for chemical sealants.