Both horticultural and industrial vermiculite in exfoliated form generally fall under this heading, but the grade, particle size, and packaging may influence the specific HTS subheading. Importers should confirm the intended use and physical specification with their customs broker, as some horticultural mineral media may trigger additional USDA APHIS review at the port of entry.

Lightweight expanded clay aggregate (LECA) is produced by firing clay at high temperatures until it expands into porous pellets. It is used as a drainage layer in green roofs, as a hydroponic growing medium, and as lightweight structural fill. Growing demand from sustainable construction and urban farming has increased import volumes, with production concentrated in Europe and parts of Asia.