Product classification

HS code for Flint: 2517.10

Pebbles, gravel, broken or crushed stone, of a kind commonly used for concrete aggregates, for road metalling or for railway or other ballast, shingle and flint, whether or not heat-treated.

Classification of flint under HS 2517.10

Flint is classified under HS code 2517.10. This code is part of Chapter 25, which encompasses salt, sulfur, earths, and stone, as well as plastering materials, lime, and cement. Specifically, heading 2517 covers pebbles, gravel, and broken or crushed stone of a kind commonly used for concrete aggregates, road metalling, or railway ballast. Flint is a hard, sedimentary cryptocrystalline form of the mineral quartz, categorized as a variety of chert. When flint is presented as pebbles or in a crushed state for industrial or construction purposes, it is classified here. The classification applies whether the material is in its natural state or has been subjected to heat treatment to enhance its physical properties for use in construction or as a grinding medium. This heading also includes macadam of slag, dross, or similar industrial waste, but flint is specifically mentioned in the context of natural stone aggregates. The material must not be worked into specific shapes like blocks or slabs, as that would move the classification to Chapter 68. The granular or pebble-like form is essential for classification under 2517, as it reflects the intended use in bulk construction or industrial processing rather than ornamental masonry.

Covers
  • Natural flint pebbles for industrial grinding
  • Crushed flint for use in road construction aggregates
  • Flint gravel used as railway ballast
  • Heat-treated flint for specialized concrete mixes
  • Unworked flint stones found in sedimentary deposits
Also under 2517.10
  • ASTM C33 concrete aggregate
  • DOT-approved road base gravel
  • railway track ballast
  • decorative garden pebbles
  • crushed granite for driveways

Codes often confused with 2517.10

Common mistake. Flint is sometimes misclassified under HS code 2506, which covers quartz and quartzite. While flint is a variety of quartz, heading 2517 is more specific when the material is used as an aggregate or ballast. Another potential error is classification under HS code 7103 if the flint is of a quality considered a semi-precious stone; however, industrial flint rarely meets these criteria. Additionally, flint used specifically as a "flint" for lighters is often classified under 3606.90 as a ferro-cerium alloy, which is a chemical product rather than the natural stone.

25.06Quartz; (other than natural sands), quartzite, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape25.17Pebbles, gravel, crushed stone for concrete aggregates for road or railway ballast, shingle or flint; macadam of slag, dross etc tarred granules, chippings, powder of stones of heading no. 2515 and 251671.03Precious (excluding diamond) and semi-precious stone; worked, graded, not strung, mounted, set; ungraded precious (excluding diamond) and semi-precious stone, temporarily strung for convenience of transport3606.90Ferro-cerium and other pyrophoric alloys in all forms; articles of combustible materials n.e.c. in chapter 36

Top exporters and importers of HS 251710 (the code used for flint), 2025

In 2025, the largest exporter of HS 251710 (the code used for flint) in UN Comtrade data was Norway, with 13% of world exports; the largest importer in UN Comtrade data was Singapore, with 12% of world imports. The United Arab Emirates 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 31% of its exports here ($75M, CEPII BACI), so it may rank higher.

Figures cover everything classified under HS 251710, not only flint.

Top exporters 2025 · share of world exports

  1. 1 Norway $268M
  2. 2 United Arab Emirates* ~$237M
  3. 3 France $137M

The United Arab Emirates 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 31% of its exports here ($75M, CEPII BACI), so it may rank higher.

World total: $2.1B Reported figures on UN Comtrade ↗

Top importers 2025 · share of world imports

  1. 1 Singapore $308M
  2. 2 United States $279M
  3. 3 Netherlands $274M

World total: $2.5B 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 flint

Brazil classifies flint under NCM 2517.10.00: HS 2517.10 with 00 added.

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

Questions about flint

What is the HS code for Flint?

The HS code for Flint is 251710 (Pebbles, gravel, broken or crushed stone; of a kind commonly used for concrete aggregates, for road metalling or for railway or other ballast, shingle and flint, whether or not heat-treated).

How do I classify Flint for customs?

Flint is classified under HS code 251710 — Pebbles, gravel, broken or crushed stone; of a kind commonly used for concrete aggregates, for road metalling or for railway or other ballast, shingle and flint, whether or not heat-treated. This is a 6-digit subheading level code.

What is the HS code for natural flint?

Natural flint, when used as gravel or aggregate, is classified under HS code 2517.10.

Is flint for lighters classified here?

No, "flints" for lighters are typically made of ferro-cerium and are classified under HS code 3606.90, not as natural stone.

Which countries are the top exporters of flint (HS 251710)?

In 2025, the top exporters of HS 251710 (the code used for flint) in UN Comtrade data were Norway ($268M, 13% of world exports), the United Arab Emirates (about $237M) and France ($137M). World exports came to about $2.1B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). The United Arab Emirates 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 31% of its exports here ($75M, CEPII BACI), so it may rank higher.

Which countries are the top importers of flint (HS 251710)?

In 2025, the top importers of HS 251710 (the code used for flint) in UN Comtrade data were Singapore ($308M, 12% of world imports), the United States ($279M) and the Netherlands ($274M). World imports came to about $2.5B, 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 Flint the same in all countries?

The base HS code 251710 for Flint 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 flint in Brazil?

In Brazil, flint (HS 251710) is classified under NCM 2517.10.00.