HS code · 6-digit subheading
HS Code 2521.00 – Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement
HS code 2521.00 is the 6-digit subheading for limestone flux, limestone and other calcareous stone, of a kind used for the manufacture of lime or cement. It is used for limestone flux, cement-grade limestone, lime-grade limestone, crushed calcareous stone and metallurgical limestone.
What HS 2521.00 covers
This HS code covers limestone and other calcareous stones specifically intended for use as a flux in metallurgy or as a primary raw material for manufacturing lime or cement. This is a high-volume bulk commodity in international trade, essential for heavy industries globally. Major importers are typically countries with significant steel production (requiring limestone as a flux to remove impurities) or robust construction sectors that rely on cement manufacturing. Exporters are nations with abundant limestone reserves and the infrastructure for large-scale quarrying and transportation. Key aspects of its trade include the purity of the calcium carbonate, the presence of impurities like silica or magnesium, and its physical characteristics (e.g., size, hardness) which affect its suitability for specific industrial processes. The global demand for this material is directly tied to industrial output and infrastructure development, making it a foundational commodity for modern economies.
- Covers
- Limestone flux
- Cement-grade limestone
- Lime-grade limestone
- Crushed calcareous stone
- Metallurgical limestone
- Agricultural limestone
- High-calcium limestone
- Examples
- Carmeuse Limestone
- Graymont Limestone
- Lhoist Limestone
- Vulcan Materials Limestone
Codes often confused with 2521.00
Common mistake. This code is often confused with other limestone categories, such as 2517 (pebbles, gravel, crushed stone for concrete) or 2515 (marble, travertine, ecaussine for monumental/building stone), because 252100 is specifically for industrial uses like flux, lime, or cement production. It could also be mistaken for dolomite (251810) if the magnesium content is significant, but 252100 is primarily calcium carbonate.
Top exporters and importers of HS code 252100, 2025
In 2025, the largest exporter of HS code 252100 in UN Comtrade data was the United Arab Emirates, with about 54% of world exports; the largest importer in UN Comtrade data was India, with 54% of world imports. Taiwan 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 20% of its imports here ($18M, CEPII BACI), so it may also belong among the top importers.
Top exporters 2025 · share of world exports
- 1 United Arab Emirates* ~$591M 54% of world exports · partner records ↗
- 2 Japan $74M 6.8% of world exports
- 3 India $67M 6.1% of world exports
World total: $1.1B Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 India $706M 54% of world imports
- 2 Bangladesh* ~$85M 6.5% of world imports · partner records ↗
- 3 Netherlands $49M 3.8% of world imports
Taiwan 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 20% of its imports here ($18M, CEPII BACI), so it may also belong among the top importers.
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 marked * did not, so their figures add up what other countries recorded trading with them, and their exports are valued at buyers' CIF prices. 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 2521.00
Brazil does not split HS 2521.00: its NCM code is 2521.00.00.
All Brazil NCM codes in heading 25.21 →
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text is official; the English is our translation.
Questions about HS 2521.00
What is HS code 252100?
HS code 252100 is a 6-digit subheading in the Harmonized System that covers: Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement. This HS code covers limestone and other calcareous stones specifically intended for use as a flux in metallurgy or as a primary raw material for manufacturing lime or cement. This is a high-volume bulk commodity in international trade, essential for heavy industries globally. Major importers are typically countries with significant steel production (requiring limestone as a flux to remove impurities) or robust construction sectors that rely on cement manufacturing. Exporters are nations with abundant limestone reserves and the infrastructure for large-scale quarrying and transportation. Key aspects of its trade include the purity of the calcium carbonate, the presence of impurities like silica or magnesium, and its physical characteristics (e.g., size, hardness) which affect its suitability for specific industrial processes. The global demand for this material is directly tied to industrial output and infrastructure development, making it a foundational commodity for modern economies.
What products fall under HS code 252100?
Limestone flux, Cement-grade limestone, Lime-grade limestone, Crushed calcareous stone, Metallurgical limestone, Agricultural limestone, High-calcium limestone
What are common misclassifications for HS code 252100?
This code is often confused with other limestone categories, such as 2517 (pebbles, gravel, crushed stone for concrete) or 2515 (marble, travertine, ecaussine for monumental/building stone), because 252100 is specifically for industrial uses like flux, lime, or cement production. It could also be mistaken for dolomite (251810) if the magnesium content is significant, but 252100 is primarily calcium carbonate.
Which countries are the top exporters of goods under HS code 252100?
In 2025, the top exporters of HS code 252100 in UN Comtrade data were the United Arab Emirates (about $591M, 54% of world exports), Japan ($74M) and India ($67M). World exports came to about $1.1B, 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 goods under HS code 252100?
In 2025, the top importers of HS code 252100 in UN Comtrade data were India ($706M, 54% of world imports), Bangladesh (about $85M) and the Netherlands ($49M). World imports came to about $1.3B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Taiwan 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 20% of its imports here ($18M, CEPII BACI), so it may also belong among the top importers.
How is HS code 252100 structured?
HS code 252100 is a 6-digit subheading under the Harmonized System. The first 2 digits (25) identify the chapter, digits 3-4 (21) identify the heading, and digits 5-6 (00) specify the subheading. This code is standardized globally by the World Customs Organization.
What is the Brazil NCM code for HS code 252100?
In Brazil, HS code 252100 is NCM 2521.00.00. The last two digits are 00 because Brazil does not split this HS code further.