Engineered from premium aluminum oxide, our ultra-thin, premium Aluminum Oxide Separating Discs are only 0.025” thick (0.635 mm) and deliver fast, precise cutting with minimal material loss. Designed to cut cleanly on the edge and both sides, they offer exceptional control on all precious metals, including gold, silver, platinum, and palladium. Aluminum Oxide Separating Discs generally run cooler than Silicon Carbide Discs. Measure 7/8” in diameter by 0.025” thick ( 24 mm x 0.64 mm approx.) and have 5/64”" arbor holes. Used with miniature mandrels that have 1/16” dia. screws (see related products below). Maximum speed: 25,000 RPM.