Definition

• Silver coins with a substantial amount of copper, such as billon coins, can become brittle after lying in the soil for centuries. Changes in metal microstructure are caused by corrosion aging. Usually silver resists corrosion. If the silver surface is porous it is easily damaged once copper in the coin has vanished. Such coins can become covered with green corrosion, and be mistaken for a copper coin.

Quelle

• Numiscadero Spanish to English Glossary (Gary Beals)

Beziehungen