C | As | Pb | Cd | Cr | Cu | Zn | Hg |
Lower | +0.862 | −0.670 | +0.508 | −0.862 | +0.492 | +0.998* | +0.862 |
Lower middle | +0.793 | +0.366 | +0.149 | −0.953 | +0.149 | +0.827 | −0.149 |
Middle | +0.101 | +0.164 | +0.619 | +0.084 | +1* | +0.187 | −0.5 |
High | −0.904 | −0.908 | −0.188 | +0.757 | −1* | +0.674 | −0.866 |