Section 13 Articles of stone, plaster,cement,asbestos, mica or similar materials; ceramic products; glass and glassware 70 Glass and glassware 70 02 Glass in balls, rods or tubes, unworked 70 02 31 Tubes of fused quartz or other fused silica, unworked Commodity Code Description 70 02 31 00 Tubes of fused quartz or other fused silica, unworked 70 02 31 10 Of a kind used to manufacture vacuum tubes 70 02 31 90 Other
