From: A methodological approach to estimate soil corrosivity for archaeological copper alloy artefacts
Corrosion type | Characteristics | Corrosion percentage | Group |
---|---|---|---|
Almost no corrosion | Almost all of metal is retained | <Â 10 | G-1 |
Minor corrosion | Thin internal corrosion layer is exist | 10–30 | G-2 |
Considerable corrosion | Considerable internal corrosion layer is exist | 30–50 | G-3 |
Almost severe corrosion | Internal corrosion layer more than half of cross section | 50–70 | G-4 |
Major corrosion | Small part of metal is retained | 70–90 | G-5 |
Almost no metal core | Almost all metal has been altered to corrosion products | >Â 90 | G-6 |