| 1. | Loosening the material |
| 2. | Bringing the material to the surface (collecting) |
| 3. | Transporting to a new location |
| 4. | Further processing at the new location |
| - | Concentrates on step 1 |
| - | Step 2 is skipped |
| - | Step 3 is partly left to nature |
| - | Step 4 is left to nature |