| Class numbers | Pre-fertilizers | Numbers of particles found |
| 1 | clay | 2 |
| 2 | lime | 1 |
| 3 | fennel debris | 4 |
| 4 | potassium sulphate | 2 |
| 5 | newberyite | 4 |
| 6 | potassium chloride | 1 |
| 7 | salt (ClNa) | 0 |