Crucibles and kiln furniture from China
Refractory ceramic goods from China other than bricks, such as clay-graphite and silicon carbide crucibles, kiln shelves and props, saggars, nozzles and tubes, pay 4% UK duty on all 6 lines of heading 6903, with no anti-dumping duty; listed silicon carbide reactor tubes can be suspended to 0%. Composition, maximum temperature and thermal shock resistance decide use.
Graphite and silicon carbide crucibles, kiln shelves, saggars, nozzles and refractory tubes from China pay 4% UK duty. Grades and thermal shock checks.

4% duty
Read from the UK Trade Tariff on 27 September 2026, heading 6903 covers other refractory ceramic goods, such as retorts, crucibles, muffles, nozzles, plugs, supports, cupels, tubes, pipes, sheaths, rods and slide gates. All 6 lines carried 4% on goods from China, split by free carbon and alumina content, with no anti-dumping measure.
Under 6903 90 90 90, silicon carbide reactor tubes and holders with a softening point of 1,400 °C or higher have a 0% suspension to 31 December 2028; the separate line 6903 90 90 40, for listed silicon carbide reactor tubes and holders with a maximum service temperature of 1,370 °C or more, carries 4%.
Refractory bricks and blocks are heading 6902 (see our refractory bricks guide), and laboratory ceramics 6909 (see our technical and laboratory ceramics guide); confirm the commodity code.
| Goods | Commodity code | Duty | Anti-dumping duty on China |
|---|---|---|---|
| Over 50% free carbon (such as clay-graphite crucibles) | 6903 10 00 00 | 4% | None |
| Over 50% alumina or alumina-silica, under 45% alumina | 6903 20 10 00 | 4% | None |
| Over 50% alumina or alumina-silica, 45% or more alumina | 6903 20 90 00 | 4% | None |
| Other, over 25% but not over 50% free carbon | 6903 90 10 00 | 4% | None |
| Listed silicon carbide reactor tubes and holders, 1,370 °C or more | 6903 90 90 40 | 4% | None |
| Other (such as silicon carbide kiln furniture) | 6903 90 90 90 | 4%; listed SiC reactor tubes 0% to 2028 | None |
Safety in use
A crucible that cracks in a furnace releases molten metal, so buyers in foundries, jewellery workshops and laboratories specify the maximum service temperature, the metal melted, preheating and the furnace type, and reject pieces with cracks or laminations.
Specifying refractory goods
Specify material (clay-graphite, silicon carbide, alumina, mullite, cordierite), shape and dimensions or capacity, maximum service temperature, bulk density and apparent porosity, cold crushing strength, thermal shock resistance, glaze or anti-oxidation coating, and packing that stops chipping.
Worked duty example
Take a hypothetical order of 1,000 clay-graphite crucibles, entered under 6903 10 00 00: £18,000 free on board plus £1,600 of freight and insurance gives a customs value of £19,600. The 4% duty on crucibles comes to £784, and import VAT is 20% of £20,384, which is £4,076.80. If you are VAT-registered you normally reclaim the £4,076.80, leaving £784 as the real cost at the border. Step by step: UK import duty and VAT.
Inspection checklist
Body: tap-test and inspect each piece for cracks, laminations and chips, and check dimensions and wall thickness.
Properties: ask for bulk density, porosity and composition test results per batch, and trial a sample in your furnace.
Packing: check each piece is separated and cushioned, and cartons are strong enough for the weight.
What goes wrong
Refractory goods fail on thermal shock, oxidation and breakage. Crucibles crack on first heating, graphite oxidises and thins the wall, kiln shelves warp at temperature, and pieces arrive chipped from poor packing.
Trial samples in service conditions and inspect before shipping. See our quality inspection guide.
Cambridge China Bridge sources crucibles, kiln furniture and refractory parts for UK foundries, potteries and labs, checking the maker's material testing first. See factory verification.
Frequently asked questions
What is the UK import duty on crucibles from China?
Read from the UK Trade Tariff on 27 September 2026, refractory ceramic goods of heading 6903, including crucibles, carried 4% from China.
Is there a duty suspension on silicon carbide tubes?
Yes, for silicon carbide reactor tubes and holders with a softening point of 1,400 °C or higher under 6903 90 90 90, to 31 December 2028.
Are refractory bricks in heading 6903?
No. Refractory bricks and blocks are heading 6902.
What should I check first?
Maximum service temperature, thermal shock resistance and a crack-free body.