Section 13 Articles of stone, plaster,cement,asbestos, mica or similar materials; ceramic products; glass and glassware 68 Articles of stone, plaster, cement, asbestos, mica or similar materials 68 04 Millstones, grindstones, grinding wheels and the like, without frameworks, for grinding, sharpening, polishing, trueing or cutting, hand sharpening or polishing stones, and parts thereof, of natural stone, of agglomerated natural or artificial abrasives, or of ceramics, with or without parts of other materials Commodity Code Description 68 04 10 - Millstones and grindstones for milling, grinding or pulping 68 04 21 - - Of agglomerated synthetic or natural diamond 68 04 22 - - Of other agglomerated abrasives or of ceramics 68 04 23 - - Of natural stone 68 04 30 - Hand sharpening or polishing stones