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 |