6903 Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods (excl. those of siliceous fossil meals or of similar siliceous earths, and refractory bricks, blocks, tiles and similar refractory ceramic constructional goods)

6903 (01/1988-..) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods (excl. those of siliceous fossil meals or of similar siliceous earths, and refractory bricks, blocks, tiles and similar refractory ceramic constructional goods) 69031000 (01/1988-..) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods, containing, by weight, > 50% graphite, other carbon or a mixture thereof (excl. refractory bricks, blocks, tiles and similar refractory ceramic constructional goods) 69032010 (01/1988-..) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods, containing, by weight, < 45% of alumina and > 50% of silica (excl. refractory bricks, blocks, tiles and similar refractory ceramic constructional goods) 69032090 (01/1988-..) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods, containing, by weight, >= 45% of alumina and > 50% of silica (excl. refractory bricks, blocks, tiles and similar refractory ceramic constructional goods) 69039010 (01/1988-..) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods, containing > 25 to 50% graphite or other carbon or a mixture thereof (excl. refractory bricks, blocks, tiles and similar refractory ceramic constructional goods) 69039020 (01/1994-12/2003) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods, containing by weight, singly or together, < 50% of the elements Mg, Ca or Cr, expressed as MgO, CaO or Cr2O3 (excl. refractory bricks, blocks, tiles and similar refractory ceramic constructional goods) 69039080 (01/1994-12/2003) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods (excl. those of siliceous fossil meals or of similar siliceous earths, articles of heading 6902, articles containing carbon, alumina, silica, or the elements Mg, Ca or Cr of subheading 6903.10.00 to 6903.90.20) 69039090 (01/2004-..) Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods (excl. those of siliceous fossil meals or of similar siliceous earths, articles of heading 6902, articles containing carbon, alumina or silica of subheading 6903.10.00 and 6903.90.10)