Salt, Sulfur, Stone, Lime & Cement

Chapter 25 covers minerals in their natural state or after washing, crushing, grinding, or calcination that does not change their essential character. Once a mineral undergoes chemical processing that produces a defined compound — such as aluminum oxide produced from bauxite by the Bayer process — it typically moves to the inorganic chemicals chapter. The chapter notes and the relevant heading texts govern the boundary.

While asbestos remains classifiable under heading 2524, its importation is subject to EPA restrictions under the Toxic Substances Control Act (TSCA). Most forms of asbestos are effectively banned from import for most uses. Importers must verify compliance with EPA TSCA requirements before any shipment, and CBP coordinates with EPA on admissibility.

Certain dimension stone products, particularly from specific origins, have been subject to antidumping or countervailing duty orders. Importers should check the current scope of any active orders against the specific tariff line and country of origin, as coverage can be narrow and origin-specific.