Ore processing - Industrial-Craft-Wiki
Dust is the final pre-smelting state and requires no further processing, though it may have other uses (creating alloys like Bronze for example).. Specific yields. Ore washing (stage 2) may be skipped (the red final column below), in which case the centrifuge (stage 3) will also yield Stone Dust in addition to its usual products (which the ore washer would normally have produced).