2843.10.00.00 - Colloidal precious metals

This category, HTS 2843.10.00.00, specifically covers colloidal precious metals. Colloidal precious metals are finely dispersed metallic particles suspended in a liquid medium, often water or organic solvents. These dispersions are characterized by particle sizes typically in the nanometer range, which imparts unique physical and chemical properties. Examples include colloidal gold, colloidal silver, and colloidal platinum, which find applications in areas such as catalysis, medicine, and electronics due to their increased surface area and reactivity.

Unlike its sibling categories, which classify chemical compounds and amalgams of precious metals, this heading is reserved exclusively for the *colloidal* form. For instance, while "silver compounds" (2843.20.00.00) would include substances like silver nitrate or silver halides, colloidal silver would fall under 2843.10.00.00. Similarly, "gold compounds" (2843.30.00.00) encompass gold salts and oxides, whereas gold in a colloidal suspension is classified here. The key differentiator is the physical state and dispersion method of the precious metal.

As this is a leaf node within the HTS, there are no further subdivisions. Therefore, accurate classification within this heading relies on the determination that the product is indeed a precious metal in a colloidal form, rather than a chemically bonded compound or an amalgam. The presence of precious metals such as gold, silver, platinum, palladium, iridium, rhodium, ruthenium, and osmium is a prerequisite, with the defining characteristic being their dispersion as ultra-fine particles within a liquid matrix.