Product classification

HS code for Silica refractories: 6903.20

Refractory ceramic goods, containing by weight more than 50% of alumina or of a mixture or compound of alumina and of silica, excluding those of siliceous fossil meals or similar earths.

Classification of silica refractories under HS 6903.20

Silica refractories, excluding bricks and structural shapes, are classified under HS code 6903.20. This classification is part of Chapter 69 (Ceramic products) and heading 6903, which covers "Other refractory ceramic goods." This heading is distinct from 6902 because it includes functional industrial items such as retorts, crucibles, muffles, nozzles, plugs, and supports, rather than constructional goods like bricks. Subheading 6903.20 specifically applies to these items when they contain more than 50% by weight of alumina or a mixture of alumina and silica. These products are vital in metallurgical, chemical, and glass-making processes where materials must remain inert and stable at extreme temperatures. The classification is determined by the chemical composition (silica/alumina content) and the fact that the items are fired ceramic refractory components.

Covers
  • Silica-alumina crucibles
  • Refractory ceramic muffles
  • Silica-based casting nozzles
  • Refractory tubing and rods
  • Ceramic kiln furniture containing >50% silica/alumina
  • Foundry ladles and stoppers
Also under 6903.20
  • Morgan Advanced Materials alumina crucibles
  • Saint-Gobain ceramic nozzles
  • CoorsTek technical ceramics
  • Kyocera industrial ceramic components

Codes often confused with 6903.20

Common mistake. These items are often confused with HS code 6902.20. The distinction lies in the application: 6902 is for constructional goods (bricks, tiles), while 6903 is for laboratory or industrial equipment (cruicibles, tubes). Another misclassification involves HS code 7017.10, which covers laboratory glassware made of fused silica. If the item is a fired ceramic (opaque, crystalline structure), it belongs in 6903; if it is fused silica glass (transparent or translucent, non-crystalline), it belongs in 7017. Finally, items made of carbon-bonded silica might be misclassified under 6903.10 if the graphite content is predominant.

6902.20Refractory bricks, blocks, tiles and similar refractory ceramic constructional goods; containing by weight more than 50% of alumina (Al2o3), of silica (SiO2) or of a mixture or compound of these69.02Refractory bricks, blocks, tiles and similar refractory ceramic constructional goods; other than those of siliceous fossil meals or similar siliceous earths69.03Ceramic goods; (e.g. retorts, crucibles, muffles, nozzles, plugs, supports cupels, tubes, pipes, sheaths, rods and slide gates) excluding those of siliceous fossil meals or of similar siliceous earths7017.10Glassware; laboratory, hygienic or pharmaceutical, whether or not graduated or calibrated, of fused quartz or other fused silica70.17Laboratory, hygienic or pharmaceutical glassware, whether or not graduated or calibrated6903.10Refractory ceramic goods; containing, by weight, more than 50% of free carbon, excluding those of siliceous fossil meals or similar earths

Top exporters and importers of HS 690320 (the code used for silica refractories), 2025

In 2025, the largest exporter of HS 690320 (the code used for silica refractories) in UN Comtrade data was China, with 13% of world exports; the largest importer in UN Comtrade data was the United States, with 15% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.

Figures cover everything classified under HS 690320, not only silica refractories.

Top exporters 2025 · share of world exports

  1. 1 China $160M
  2. 2 Czechia $130M
  3. 3 United States $128M

World total: $1.3B Reported figures on UN Comtrade ↗

Top importers 2025 · share of world imports

  1. 1 United States $192M
  2. 2 South Korea $72M
  3. 3 Italy $69M

World total: $1.3B Reported figures on UN Comtrade ↗

How these figures are built

109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries that did not report are estimated from what other countries recorded trading with them. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).

Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.

Brazil NCM codes for silica refractories

Brazil splits HS 6903.20 into 4 NCM codes. Pick the one that matches your product:

  • 6903.20.10Crucibles over 50% alumina or alumina-silica
  • 6903.20.20Lids and plugs over 50% alumina or alumina-silica
  • 6903.20.30Tubes over 50% alumina or alumina-silica
  • 6903.20.90Other refractories over 50% alumina/alumina-silica

Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.

Questions about silica refractories

What is the HS code for Silica refractories?

The HS code for Silica refractories is 690320 (Refractory ceramic goods; containing by weight more than 50% of alumina or of a mixture or compound of alumina and of silica, excluding those of siliceous fossil meals or similar earths). Functional silica-based refractory goods like crucibles and nozzles are classified under HS code 6903.20.

How do I classify Silica refractories for customs?

Silica refractories is classified under HS code 690320 — Refractory ceramic goods; containing by weight more than 50% of alumina or of a mixture or compound of alumina and of silica, excluding those of siliceous fossil meals or similar earths. This is a 6-digit subheading level code.

How do I distinguish between ceramic refractories and silica glassware?

Ceramic refractories (6903) are typically opaque and fired from clay or mineral mixes, while silica glassware (7017) is made from melted (fused) quartz and is usually transparent or translucent.

Which countries are the top exporters of silica refractories (HS 690320)?

In 2025, the top exporters of HS 690320 (the code used for silica refractories) in UN Comtrade data were China ($160M, 13% of world exports), Czechia ($130M) and the United States ($128M). World exports came to about $1.3B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.

Which countries are the top importers of silica refractories (HS 690320)?

In 2025, the top importers of HS 690320 (the code used for silica refractories) in UN Comtrade data were the United States ($192M, 15% of world imports), South Korea ($72M) and Italy ($69M). World imports came to about $1.3B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.

Is the HS code for Silica refractories the same in all countries?

The base HS code 690320 for Silica refractories is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.

What is the NCM code for silica refractories in Brazil?

Brazil splits HS 690320 into 4 NCM codes, so the right one for silica refractories depends on the product's details: 6903.20.10 (Crucibles over 50% alumina or alumina-silica), 6903.20.20 (Lids and plugs over 50% alumina or alumina-silica), 6903.20.30 (Tubes over 50% alumina or alumina-silica), 6903.20.90 (Other refractories over 50% alumina/alumina-silica).