Section 13 Articles of stone, plaster,cement,asbestos, mica or similar materials; ceramic products; glass and glassware 69 Ceramic products 69 09 Ceramic wares for lab.,chem.or technical uses;agriculture ;conveyance or goods packing 69 09 12 Articles having a hardness equivalent to 9 or more on the Mohs scale Commodity Code Description 69 09 12 00 Articles having a hardness equivalent to 9 or more on the Mohs scale