Product classification
HS code for Sintered dolomite: 2518.20
Dolomite, calcined or sintered, including dolomite roughly trimmed, or merely cut by sawing or otherwise into blocks or slabs of rectangular (including square) shape.
Classification of sintered dolomite under HS 2518.20
Sintered dolomite is classified under HS code 2518.20, which specifically addresses dolomite that has undergone a calcination or sintering process. This classification falls within Chapter 25, covering salt, sulfur, earths, and stone. The process of sintering involves heating raw dolomite—a natural calcium magnesium carbonate—to extremely high temperatures, typically exceeding 1,500 degrees Celsius. This thermal treatment, often referred to as "dead-burning," drives off carbon dioxide and results in a dense, chemically stable refractory material composed primarily of calcium and magnesium oxides. Under GRI 1, the classification is dictated by the specific description in heading 25.18. While raw dolomite is classified under 2518.10, the sintered variety is distinguished by its physical transformation into a hard, granular material that is resistant to hydration and thermal shock. This makes it ideal for use as a refractory lining in steel-making furnaces, particularly in basic oxygen furnaces and electric arc furnaces. The material must remain in a granular or roughly blocked state to stay within this heading; if it is further processed into finished refractory bricks, it would move to Chapter 69.
- Covers
- Dead-burned dolomite
- Calcined dolomite
- Refractory grade sintered dolomite
- Sintered dolomite grains
- Sintered dolomite blocks (roughly trimmed or sawn)
- Also under 2518.20
- RHI Magnesita Dolime
- Vesuvius Refractories Dolime
- Lhoist Dolime
- Carmeuse Dolime
Codes often confused with 2518.20
Common mistake. Sintered dolomite is often confused with 2518.10 (raw dolomite) or 2522.20 (slaked lime). The primary difference is the heat treatment; 2518.10 has not been sintered, and 2522.20 refers to calcium hydroxide. It is also sometimes misclassified under 3816.00, which covers refractory cements and mortars, but 2518.20 is reserved for the mineral itself before it is mixed into a prepared cement.
Top exporters and importers of HS 251820 (the code used for sintered dolomite), 2025
In 2025, the largest exporter of HS 251820 (the code used for sintered dolomite) in UN Comtrade data was Belgium, with 42% of world exports; the largest importer in UN Comtrade data was the Netherlands, with 16% of world imports. Vietnam did not report 2025 data, and its estimate from partner records misses its trade with other countries that did not report: in 2024 that was 47% of its exports here ($8.9M, CEPII BACI), so it may also belong among the top exporters.
Figures cover everything classified under HS 251820, not only sintered dolomite.
Top exporters 2025 · share of world exports
- 1 Belgium $65M 42% of world exports
- 2 United States $14M 9.1% of world exports
- 3 Italy $12M 8.1% of world exports
Vietnam did not report 2025 data, and its estimate from partner records misses its trade with other countries that did not report: in 2024 that was 47% of its exports here ($8.9M, CEPII BACI), so it may also belong among the top exporters.
World total: $154M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Netherlands $28M 16% of world imports
- 2 Sweden $24M 14% of world imports
- 3 Japan $14M 7.9% of world imports
World total: $175M 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 code for sintered dolomite
Brazil classifies sintered dolomite under NCM 2518.20.00: HS 2518.20 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about sintered dolomite
What is the HS code for Sintered dolomite?
The HS code for Sintered dolomite is 251820 (Dolomite, calcined or sintered; including dolomite roughly trimmed, or merely cut by sawing or otherwise into blocks or slabs of rectangular (including square) shape). The HS code for sintered or calcined dolomite is 2518.20.
How do I classify Sintered dolomite for customs?
Sintered dolomite is classified under HS code 251820 — Dolomite, calcined or sintered; including dolomite roughly trimmed, or merely cut by sawing or otherwise into blocks or slabs of rectangular (including square) shape. This is a 6-digit subheading level code.
Is sintered dolomite the same as refractory brick?
No, sintered dolomite is the raw material used to make refractory linings. Once it is shaped and fired into bricks, it is classified under HS code 6902.10.
Which countries are the top exporters of sintered dolomite (HS 251820)?
In 2025, the top exporters of HS 251820 (the code used for sintered dolomite) in UN Comtrade data were Belgium ($65M, 42% of world exports), the United States ($14M) and Italy ($12M). World exports came to about $154M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Vietnam did not report 2025 data, and its estimate from partner records misses its trade with other countries that did not report: in 2024 that was 47% of its exports here ($8.9M, CEPII BACI), so it may also belong among the top exporters.
Which countries are the top importers of sintered dolomite (HS 251820)?
In 2025, the top importers of HS 251820 (the code used for sintered dolomite) in UN Comtrade data were the Netherlands ($28M, 16% of world imports), Sweden ($24M) and Japan ($14M). World imports came to about $175M, 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 Sintered dolomite the same in all countries?
The base HS code 251820 for Sintered dolomite 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 sintered dolomite in Brazil?
In Brazil, sintered dolomite (HS 251820) is classified under NCM 2518.20.00.