| 2528 | | Natural borates and concentrates thereof (calcined or not), but not including borates separated from natural brine; natural boric acid containing not more than 85 percent of H3BO3 calculated on the dry weight: | | | | |
| 2610.00.00 | 20 | Having a chromium content equivalent to not more than 40 percent chromic oxide (Cr2O3) | t Cr2O3 t | | | |
| 2610.00.00 | 40 | Having a chromium content equivalent to more than 40 percent but less than 46 percent chromic oxide (Cr2O3) | t Cr2O3 t | | | |
| 2610.00.00 | 60 | Having a chromium content equivalent to 46 percent or more chromic oxide (Cr2O3) | t Cr2O3 t | | | |
| 2821 | | Iron oxides and hydroxides; earth colors containing 70 percent or more by weight of combined iron evaluated as Fe2O3: | | | | |
| 6902.10 | | Containing by weight, singly or together, more than 50 percent of the elements magnesium, calcium or chromium, expressed as MgO, CaO or Cr2O3: | | | | |
| 6902.20 | | Containing by weight more than 50 percent of alumina (Al2O3), of silica (SiO2) or of a mixture or compound of these products: | | | | |
| 6903.20.00 | 00 | Containing by weight more than 50 percent of alumina (Al2O3) or of a mixture or compound of alumina and of silica (SiO2) | kg | Free | | 30% |
