Product classification
HS code for Diamond grinding wheels: 6804.21
Millstones, grindstones, grinding wheels and the like, of agglomerated synthetic or natural diamond.
Classification of diamond grinding wheels under HS 6804.21
Diamond grinding wheels are classified under HS code 6804.21. This code is designated for millstones, grindstones, grinding wheels, and similar articles without frameworks, used for grinding, sharpening, polishing, trueing, or cutting, made of agglomerated synthetic or natural diamond. While diamonds themselves are categorized in Chapter 71, once they are bonded or agglomerated into a specific tool shape like a wheel, they move to Chapter 68, which covers articles of stone, plaster, cement, asbestos, mica, or similar materials. The sub-heading 6804.21 specifically identifies those where the abrasive part consists of diamond. This classification is based on the function of the article as an abrasive tool and its material composition. The wheels may be bonded with resin, metal, or vitrified materials, but as long as the active abrasive component is diamond, 6804.21 remains the correct classification. This includes wheels used for precision grinding in the automotive, aerospace, and tool-making industries.
- Covers
- Resin-bonded diamond grinding wheels
- Metal-bonded diamond wheels
- Vitrified diamond wheels
- Diamond honing stones
- Diamond cutting discs (without frameworks)
- Also under 6804.21
- Norton Abrasives diamond wheels
- Tyrolit diamond cutting discs
- 3M Cubitron diamond abrasives
- Bosch diamond saw blades
Codes often confused with 6804.21
Common mistake. A common misclassification occurs with HS code 8207, which covers interchangeable tools for hand tools or machine tools. However, 6804 specifically excludes tools with a working part of diamond if they are not agglomerated wheels or stones. Another error is using 7105, which is for the diamond dust itself before it has been manufactured into a wheel. Furthermore, if the wheel has a permanent framework or is part of a specific machine, it might be confused with Chapter 84 machinery parts.
Top exporters and importers of HS 680421 (the code used for diamond grinding wheels), 2025
In 2025, the largest exporter of HS 680421 (the code used for diamond grinding wheels) in UN Comtrade data was China, with 14% of world exports; the largest importer in UN Comtrade data was China, with 16% 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 680421, not only diamond grinding wheels.
Top exporters 2025 · share of world exports
- 1 China $253M 14% of world exports
- 2 South Korea $236M 13% of world exports
- 3 Italy $227M 12% of world exports
World total: $1.8B Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 China $353M 16% of world imports
- 2 United States $230M 11% of world imports
- 3 Germany $191M 8.7% of world imports
World total: $2.2B 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 diamond grinding wheels
Brazil splits HS 6804.21 into 3 NCM codes. Pick the one that matches your product:
- 6804.21.11Resin-bonded diamond wheels, under 53.34 cm
- 6804.21.19Other diamond wheels under 53.34 cm diameter
- 6804.21.90Diamond grinding wheels, 53.34 cm or more
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about diamond grinding wheels
What is the HS code for Diamond grinding wheels?
The HS code for Diamond grinding wheels is 680421 (Millstones, grindstones, grinding wheels and the like; of agglomerated synthetic or natural diamond). The HS code for diamond grinding wheels made of agglomerated natural or synthetic diamond is 6804.21.
How do I classify Diamond grinding wheels for customs?
Diamond grinding wheels is classified under HS code 680421 — Millstones, grindstones, grinding wheels and the like; of agglomerated synthetic or natural diamond. This is a 6-digit subheading level code.
Are diamond cutting discs classified here?
Yes, diamond cutting discs without frameworks are generally classified under 6804.21, provided the abrasive portion is made of agglomerated diamond.
Which countries are the top exporters of diamond grinding wheels (HS 680421)?
In 2025, the top exporters of HS 680421 (the code used for diamond grinding wheels) in UN Comtrade data were China ($253M, 14% of world exports), South Korea ($236M) and Italy ($227M). World exports came to about $1.8B, 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 diamond grinding wheels (HS 680421)?
In 2025, the top importers of HS 680421 (the code used for diamond grinding wheels) in UN Comtrade data were China ($353M, 16% of world imports), the United States ($230M) and Germany ($191M). World imports came to about $2.2B, 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 Diamond grinding wheels the same in all countries?
The base HS code 680421 for Diamond grinding wheels 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 diamond grinding wheels in Brazil?
Brazil splits HS 680421 into 3 NCM codes, so the right one for diamond grinding wheels depends on the product's details: 6804.21.11 (Resin-bonded diamond wheels, under 53.34 cm), 6804.21.19 (Other diamond wheels under 53.34 cm diameter), 6804.21.90 (Diamond grinding wheels, 53.34 cm or more).