Product classification
HS code for Colloidal gold: 2843.10
Colloidal precious metals, whether or not chemically defined.
Classification of colloidal gold under HS 2843.10
Colloidal gold is classified under HS code 2843.10, which falls within Chapter 28 of the Harmonized System, covering inorganic chemicals and precious metal compounds. Heading 2843 is specifically designated for colloidal precious metals, as well as inorganic or organic compounds of precious metals. Colloidal gold consists of sub-micron sized particles of gold suspended in a fluid, usually water. The classification is driven by the chemical state of the gold; it is not in a bulk metallic form but rather a stable dispersion of particles. This subheading 2843.10 covers the colloidal form of any precious metal, but it is most frequently applied to gold and silver suspensions used in medical diagnostics, electronics, and research. The technical requirement for this classification is that the gold must remain in a colloidal state, which involves specific surface chemistry to prevent the particles from aggregating.
- Covers
- Colloidal gold suspensions
- Gold nanoparticles in aqueous solution
- Colloidal silver dispersions
- Colloidal platinum
- Precious metal hydrosols
- Also under 2843.10
- Sigma-Aldrich (various nanoparticles)
- Nanopartz (gold nanoparticles)
- BBI Solutions (gold nanoparticles)
- Tanaka Kikinzoku Kogyo (precious metal chemicals)
- Johnson Matthey (catalyst precursors)
Codes often confused with 2843.10
Common mistake. Colloidal gold is sometimes misclassified under HS code 3004 if it is prepared as a medicament for therapeutic use. However, unless it is put up in measured doses or in forms for retail sale for medical purposes, 2843.10 remains the correct chemical classification. It is also confused with HS code 3206, which covers coloring matter and pigments; while colloidal gold can provide color, it is classified by its chemical nature in Chapter 28. Finally, it should not be confused with HS code 7108, which covers gold in unwrought or semi-manufactured forms like bars or powder, as the colloidal state is a distinct chemical preparation.
Top exporters and importers of HS 284310 (the code used for colloidal gold), 2025
In 2025, the largest exporter of HS 284310 (the code used for colloidal gold) in UN Comtrade data was Türkiye, with 66% of world exports; the largest importer in UN Comtrade data was the United Arab Emirates, with about 66% 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 284310, not only colloidal gold.
Top exporters 2025 · share of world exports
- 1 Türkiye $202M 66% of world exports
- 2 Romania $29M 9.4% of world exports
- 3 Italy $21M 6.7% of world exports
World total: $307M Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 United Arab Emirates* ~$202M 66% of world imports · partner records ↗
- 2 Indonesia $45M 15% of world imports
- 3 India $9.8M 3.2% of world imports
World total: $306M 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 colloidal gold
Brazil classifies colloidal gold under NCM 2843.10.00: HS 2843.10 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about colloidal gold
What is the HS code for Colloidal gold?
The HS code for Colloidal gold is 284310 (Colloidal precious metals; whether or not chemically defined). The HS code for colloidal gold and other colloidal precious metals is 2843.10.
How do I classify Colloidal gold for customs?
Colloidal gold is classified under HS code 284310 — Colloidal precious metals; whether or not chemically defined. This is a 6-digit subheading level code.
Is colloidal gold classified as a precious metal or a chemical?
Under the Harmonized System, it is classified as an inorganic chemical under Chapter 28, specifically as a colloidal precious metal in heading 2843.
Which countries are the top exporters of colloidal gold (HS 284310)?
In 2025, the top exporters of HS 284310 (the code used for colloidal gold) in UN Comtrade data were Türkiye ($202M, 66% of world exports), Romania ($29M) and Italy ($21M). World exports came to about $307M, 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 colloidal gold (HS 284310)?
In 2025, the top importers of HS 284310 (the code used for colloidal gold) in UN Comtrade data were the United Arab Emirates (about $202M, 66% of world imports), Indonesia ($45M) and India ($9.8M). World imports came to about $306M, 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 Colloidal gold the same in all countries?
The base HS code 284310 for Colloidal gold 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 colloidal gold in Brazil?
In Brazil, colloidal gold (HS 284310) is classified under NCM 2843.10.00.