Bulk Packaged 3/16 x 3/8 inch Green Cone Silicon Carbide Grinding Stone, Compare to Dremel 84922. 1/8 inch shank. Silicon Carbide Stones are used for non ferrous metals, like aluminum and brass, as well as very hard metals like carbide. Can also be used on glass, porcelain, ceramic, stones and gemstones. For use with Dremel Rotary Tools.