Harmonized System
Section V > Chapter 25 > Heading 2508 > 2508.40
Other clays
Section V > Chapter 25 > Heading 2508 > 2508.50
Andalusite, kyanite and sillimanite
Section V > Chapter 25 > Heading 2508 > 2508.70
Chamotte or dinas earths
Section V > Chapter 25 > Heading 2510
Natural calcium phosphates, natural aluminium calcium phosphates and phosphatic chalk.
Section V > Chapter 25 > Heading 2511
Natural barium sulphate (barytes); natural barium carbonate (witherite), whether or not calcined, other than barium oxide of heading 28.16.