2530 - Mineral substances not elsewhere specified or included:

This HTS category, 2530, encompasses a diverse range of mineral substances that are not specifically enumerated or included in other chapters of Section V. These are raw or processed mineral materials valued for their inherent properties, but which do not fit neatly into more specialized classifications like ores, salts, or specific types of earths and stones. The scope of this heading is broad, intended as a residual category for unclassified mineral products.

Within the broader context of Chapter 25, which deals with salt, sulfur, earths, and stone, heading 2530 serves as a catch-all for minerals not otherwise specified. Unlike headings for common salt (2501) or sulfur (2503), or more defined categories of earths and stones, 2530 captures those minerals whose primary commercial value or distinguishing characteristic places them outside those more precise groupings. It is distinct from classifications for manufactured mineral products found in later sections of the HTS.

The subcategories within 2530 further refine the classification of these residual mineral substances. For instance, 2530.10 specifically identifies vermiculite, perlite, and chlorites in their unexpanded forms, recognizing their unique physical properties and common industrial applications. Heading 2530.20 targets kieserite and natural epsom salts, distinguishing them by their specific chemical composition as natural magnesium sulfates. Finally, the residual category 2530.90 is designated for all other mineral substances not elsewhere specified or included within this heading or the HTS overall, requiring careful analysis to ensure proper classification.