Abstract: Metal polishing compositions comprising a boronated felspathoid and a suitable liquid, semi-solid or solid carrier. The boronated felspathoid has a crystal structure similar to the mineral nosean.

Abstract: A polishing process for mineral and organic ophthalmic lenses involves essentially a first step of mixing cerium oxide powder or zirconium oxide powder with (a) an alkali metal or ammonium salt of the condensation product of naphthalene sulphonic acid with formaldehyde, or of lignin sulphonic acid serving as an anionic deflocculating agent in an amount necessary to cause deflocculation, (b) an electrolyte containing a metal cation having a valency greater than 1, and (c) water, to form a slurry in which the powder is in a state of reversible flocculation. By this method the performance of the polishing powder in terms of numbers of acceptable lenses processed by each kilo of the powder is greatly improved.