Give your castings the look and feel of marble, wood, or metal with ArtMolds powders. - ArtMolds Powders - 1/2 lb, BronzeArtmolds Powders, BRNZ 325-MESH 1/2LB - This powder is a fine grade of 325 mesh, the ideal degree of fineness for cold casting. Add it to polyester or polyurethane resin, epoxy, gypsum cement, or other binders to create the authentic look and feel of a hot metal foundry casting. Following abrading and/or burnishing, the finished piece can be patinated or allowed to naturally oxidize for an antique look.