| 231 |
Manufacture of glass and glass products |
| 232 |
Manufacture of refractory products |
| 233 |
Manufacture of clay building materials |
| 234 |
Manufacture of other porcelain and ceramic products |
| 235 |
Manufacture of cement, lime and plaster |
| 236 |
Manufacture of articles of concrete, cement and plaster |
| 237 |
Cutting, shaping and finishing of stone |
| 239 |
Manufacture of abrasive products and non-metallic mineral products n.e.c. |