| 25.06 | | Quartz (other than natural sands); quartzite, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape |
| 2506.10 | 000 | Quartz |
| 2506.20 | 000 | Quartzite |
| 25.07 | | |
| 2507.00 | 000 | Kaolin and other kaolinic clays, whether or not calcined |
| 25.08 | | Other clays (not including expanded clays of heading 68.06), andalusite, kyanite and sillimanite, whether or not calcined; mullite; chamotte or dinas earths |
| 2508.10 | 000 | Bentonite |
| 2508.30 | 000 | Fire-clay |
| 2508.40 | | Other clays |
| 2508.40 | 010 | - Aluminous shale |
| 2508.40 | 090 | - Other |
| 2508.50 | 000 | Andalusite, kyanite and sillimanite |
| 2508.60 | 000 | Mullite |
| 2508.70 | 000 | Chamotte or dinas earths |
| 25.09 | | |
| 2509.00 | 000 | Chalk |
| 25.10 | | Natural calcium phosphates, natural aluminium calcium phosphates and phosphatic chalk |
| 2510.10 | 000 | Unground |
| 2510.20 | 000 | Ground |
| 25.11 | | Natural barium sulphate (barytes); natural barium carbonate (witherite), whether or not calcined, other than barium oxide of heading 28.16 |
| 2511.10 | 000 | Natural barium sulphate (barytes) |
| 2511.20 | 000 | Natural barium carbonate (witherite) |
| 25.12 | | |
Harmonized Tariff Schedule of Japans inquiry: ε
