2846.90.20.40 - Other

This HTS category, "Rare-earth oxides except cerium oxides," encompasses a variety of inorganic compounds formed by the combination of oxygen with rare-earth metals, excluding those primarily composed of cerium. These oxides are typically solid materials, often appearing as powders or crystalline substances, and are valued for their unique chemical and physical properties, such as high melting points, luminescence, and catalytic activity. They find applications in diverse industries including ceramics, electronics, glass manufacturing, and specialized catalysts.

Distinction from its sibling categories is crucial for accurate classification. While this node covers rare-earth oxides where a metal other than cerium predominates, the sibling category "Containing lanthanum as the predominant metal" (2846.90.20.05) is specifically for mixtures where lanthanum oxides are the primary component. Similarly, "Containing yttrium or scandium as the predominant metal" (2846.90.20.15) is designated for mixtures where yttrium or scandium oxides are the most significant rare-earth constituent. Therefore, this category acts as a residual for rare-earth oxide mixtures where the predominant metal is neither lanthanum, yttrium, scandium, nor cerium.

As this is a leaf node in the HTS, there are no further subcategories. Classification within this heading relies on the chemical analysis to determine the predominant rare-earth metal present in the mixture, ensuring it is not cerium, lanthanum, yttrium, or scandium. The presence of other rare-earth elements in conjunction with or as minor components to these excluded metals will place the product within this residual classification.