2819.90.00.00 - Other

This category, HTS 2819.90.00.00, encompasses chromium oxides and hydroxides that are not specifically classified under other headings within Chapter 28. Primarily, it includes various forms of chromium compounds that exhibit different oxidation states or bonding structures compared to chromium trioxide. Goods falling under this classification typically serve as pigments, catalysts, or components in various industrial processes.

The key distinction between this category and its sibling, 2819.10.00.00 (Chromium trioxide), lies in the chemical composition and oxidation state. Chromium trioxide is specifically defined by its chemical formula and is often a strong oxidizing agent with distinct properties and applications. This residual category, conversely, captures other chromium oxides (e.g., chromium(II) oxide, chromium(III) oxide) and chromium hydroxides that do not meet the precise definition of chromium trioxide.

As this is a leaf node, there are no further subcategories. Therefore, classification within 2819.90.00.00 relies on the absence of a more specific tariff designation. Importers and exporters should carefully review the chemical makeup and properties of their chromium oxide or hydroxide products to ensure they are not classifiable under the more specific heading for chromium trioxide before assigning them to this general residual category.