WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
25.13 - Pumice stone; emery; natural corundum, natural garnet and other natural abrasives, whether or not heat-treated. 2513.10 2513.20 - Pumice stone - Emery, natural corundum, natural garnet and other natural abrasives Pumice stone is a very porous variety of volcanic rock, rough to the touch and extremely light in wei ht, usually whitish or grey, but sometimes brown or red. The heading also covers cmshe pumice (bimskies). i! Emery is a dense rock formed of small hard aluminium oxide crystals mixed with iron oxide and articles of mica. It is often presented in rock form for use as an abrasive powder after simp e crushing. Crushed emery.is a dirty brown powder interspersed with occasional glittering grains; a magnet attracts the particles of iron oxide. P Natural corundum is also composed largely of aluminium oxide but, unlike emery, it is often presented in bags, in the form of more or less fine ains. Ground or crushed corundum is mainly composed of small white granules with a ew black or yellow particles. Natural corundum remains classified in this heading even if it has been heat treated. P Other natural abrasives include the tripoli known as " rotten-stone ",an ash grey product used as a mild abrasive or for polishing, and ~ a r n e (including t dust and owder) other than that of Cha ter 71. The natural abrasives of t h s aragraph remain classi led in this heahng even if they ave been heat-treated; natural garnet, or example, is sometimes heat-treated after grading to improve its capillarity and hardness. R F P The heading does not include : (a) Abrasive materials referred to in other headings of this Chapter. (b) Precious or semi-precious stones (e.g., ruby,sapphire) of heading 71.03. (c) Artificial abrasives such as artificial corundum (heading 28.18), silicon carbide (heading 28.49) and synthetic precious or semi-precious stones (heading 71.04). (d) Dust and powder of natural or synthetic precious or semi-precious stones (heading 71.05).
Notes. 1.- Except where their context or Note 4 to this Chapter otherwise requires, the headings of this Chapter cover only products which are in the crude state or which have been washed (even with chemical substances eliminating the impurities without changing the structure of the product), crushed, ground, powdered, levigated, sifted, screened, concentrated by flotation, magnetic separation or other mechanical or physical processes (except crystallisation), but not products which have been roasted, calcined, obtained by mixing or subjected to processing beyond that mentioned in each heading. The products of this Chapter may contain an added anti-dusting agent, provided that such addition does not render the product particularly suitable for specific use rather than for general use. 2.- This Chapter does not cover : (a) Sublimed sulphur, precipitated sulphur or colloidal sulphur (heading 28.02); (b) Earth colours containing 70 % or more by weight of combined iron evaluated as Fe O 2 3 (heading 28.21); (c) Medicaments or other products of Chapter 30; (d) Perfumery, cosmetic or toilet preparations (Chapter 33); (e) Dolomite ramming mix (heading 38.16); (f) Setts, curbstones or flagstones (heading 68.01); mosaic cubes or the like (heading 68.02); roofing, facing or damp course slates (heading 68.03); (g) Precious or semi-precious stones (heading 71.02 or 71.03); (h) Cultured crystals (other than optical elements) weighing not less than 2.5 g each, of sodium chloride or of magnesium oxide, of heading 38.24; optical elements of sodium chloride or of magnesium oxide (heading 90.01); (ij) Billiard chalks (heading 95.04); or (k) Writing or drawing chalks or tailors' chalks (heading 96.09). 3.- Any products classifiable in heading 25.17 and any other heading of the Chapter are to be classified in heading 25.17. 4.- Heading 25.30 applies, inter alia, to : vermiculite, perlite and chlorites, unexpanded; earth colours, whether or not calcined or mixed together; natural micaceous iron oxides; meerschaum (whether or not in polished pieces); amber; agglomerated meerschaum and agglomerated amber, in plates, rods, sticks or similar forms, not worked after moulding; jet; strontianite (whether or not calcined), other than strontium oxide; broken pieces of pottery, brick or concrete.