6903 90 — Retorts, crucibles, mufflers, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and other refractory ceramic goods (excl. those of siliceous fossil meals or similar siliceous earths, those of heading 6902, containing > 50% carbon or containing > 50% by weight of alumina [Al203] or a mixture or compound of alumina and silica [SiO2])

6903 Other refractory ceramic goods (for example, retorts, crucibles, muffles, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, bars, rods), other than those of siliceous fossil meals or of similar siliceous earths: 6903 10 – containing by weight more than 50 % of graphite or other forms of carbon or of a mixture of these products 6903 20 – containing by weight more than 50 % of alumina (Al2O3) or of a mixture or compound of alumina and of silica (SiO2) 6903 90 – other

This heading covers all refractory articles not specified or included in the preceding headings. This heading includes:

(1) Articles which are, in contrast to those described in heading 6902, often unfixed parts, such as retorts, receptacles for chemical reactions, crucibles, assay cups and similar articles intended for use in manufacture or in laboratory conditions, muffles, nozzles, plugs, nozzles of burners and similar parts of furnaces; firing capsules, supports and other parts of furnaces for the maintenance and separation of faience products during firing; casings and rods; tripods for cribings, for crucibles, even for the construction of pipes, and for use in the same form, or for the same form, (2) for the construction of tubes, or for the same form, or for the use in the construction of pipes. However, Zeger cones (ceramic combustion probes) are not included (see the HS Explanatory Note to heading 3824); they are not fired after forming.

This subgroup includes ceramic products other than silica flour or silica and refractory products of subgroup I. Throughout the Nomenclature, these articles are classified by type (bricks, tiles, sanitary products, etc.), and this classification is not affected by the nature of the ceramics used in their manufacture, with the exception of tableware, cookware, other household articles and toiletries classified in heading 6911 if they are made of porcelain, and in heading 6912 if they are made of other ceramics. (i) Porcelain means hard porcelain, soft porcelain, biscuit porcelain (including Paros) and bone porcelain. All these ceramic products are almost completely glazed, durable and almost impermeable (even if not glazed). These are white products or artificially painted, translucent (if they do not have a large wall thickness) and resonating. Solid porcelain is made from raw materials consisting of kaolin (or kaolin clays), quartz, feldspar (or feldspatoids) sometimes with the addition of calcium carbonate. It is covered with a colorless transparent glaze and then burned, as a result of which the glaze is sintered with the base. Soft porcelain contains less alumina but more silica and fluxes (such as feldspar). Bone porcelain containing less alumina also includes calcium phosphate (for example, in the form of bone ash); a translucent substance is obtained by firing at a lower temperature than that of hard porcelain. Glaze is usually applied by secondary low-temperature firing, which allows the use of a greater variety of underglaze paints. Biscuit porcelain is unglazed porcelain. Its variety, Paros porcelain (sometimes called Karari porcelain), is a special fine-grained yellowish substance containing a large amount of feldspar and often similar in appearance to Paros marble, which determined its name.

(II) Other ceramic articles Ceramic articles other than porcelain include: (A) Porous ceramic products, opaque, unlike porcelain, allowing liquid, metal objects easily leave scratches on their surface, they stick to the tongue at a break. Such ceramics include: (1) Ceramic products made of ordinary iron-containing and lime clays (brick clay). They are dull, earthy structures, usually brown, red or yellow. (2) A wide range of white or painted ceramic products (faience, majolica, delft faience, etc.). Products are porous structure, and to become impermeable, they should be glazed (for example, using transparent and opaque glazes such as white or colored metal oxides). Faijans, etc. are made of finely sifted clays mixed with water. These types of products are distinguished by a fine-grained structure obtained by firing at a higher temperature than in the case of ceramics made of ordinary clay; they differ from porcelain in that they are not completely glazed. (B) Articles of stone ceramics, which, although having a sufficiently dense structure and sufficient twer strength to provide resistance to the effects of a steel point, differ from porcelain in that they are opaque and usually only partially glazed. Products made of stone ceramics can be vitrified (impermeable) or semi-glassed. Usually they are gray or brownish due to impurities contained in the clay used as raw materials, and they are usually coated with glaze. (C) Some products, called "semi-porcelain" or "porcelain imitation", are made, decorated and glazed in such a way as to give them the appearance of porcelain. Not being completely opaque like clay pottery, or translucent like porcelain, they are slightly translucent in their thinnest parts, for example, at the base of cups. However, these products differ from real porcelain coarse-grained structure, as well as the fact that they are dull and unglassed. Under a layer of glaze, they are therefore porous and stick to the tongue at a break. In addition, a steel knife easily leaves scratches on their surface, although it should be noted that on some types of soft porcelain, steel also leaves scratch marks. Products from such an imitation of "porcelain" are not considered real porcelain. This subgroup also includes certain articles made by molding and firing from powdered steatite, etc., usually mixed with clay (e.g. kaolin), feldspar, etc., but it should be noted that many articles of such materials are intended for use in the electrical industry and are therefore included in Chapter 85. This subgroup also includes products made by burning steatite preformed by pressing. Certain ceramic articles of refractory materials (e.g., of sintered alumina) may also be included in Chapter II if they do not belong to the category of articles intended for use as refractory articles (see the HS Explanatory Note to heading 6909).

Notes

Machine translation. The original is the Russian text of the EAEU tariff, and customs goes by it; this translation is for understanding only and has no legal force.

1. This chapter includes only ceramic articles which have been fired after forming:

(a) headings 6904 to 6914 cover only those articles which are not covered in headings 6901 to 6903;

(b) articles heated to a temperature of less than 800 °C for the purpose of curing the resin, accelerating the hydration reaction or for the removal of water or other volatile components are not considered to have been burned. Such articles are excluded from Chapter 69; and

(c) ceramic articles obtained by firing inorganic non-metallic materials pre-prepared and molded, usually at room temperature. Raw materials include, inter alia, clays, silica materials including fused silica, high melting point materials such as oxides, carbides, nitrides, graphite or other forms of carbon, and in some cases binders such as refractory clays or phosphates.

2. This group does not include:

(a) the goods of heading 2844;

(b) articles of heading 6804;

(c) articles of Chapter 71 (for example, jewelry);

(d) the ceramics of heading 8113;

(e) articles of Chapter 82;

(f) electrical insulators (heading 8546) or fittings of insulating materials of heading 8547;

(g) artificial teeth (heading 9021);

(h) articles of Chapter 91 (e.g. watches not intended to be worn on or with oneself and their housings);

(ij) articles of Chapter 94 (e.g. furniture, fixtures and lighting equipment, prefabricated constructions);

(k) Articles of Chapter 95 (e.g. toys, games and sports equipment);

(l) articles of heading 9606 (e.g. buttons) or 9614 (e.g. pipes); or

(m) Articles of Chapter 97 (e.g. works of art).