Most such blemishes are harmless, and collectors prize certain kinds of discoloration. Moreover, verdigris formed by corrosion seals the metal below away from the air, thus acting as a protective layer that prevents corrosion from creeping deeper into the metal.
這些鏽蝕物大部分是良性的，有的顏色斑爛，頗受收藏者喜愛，也可以隔絕空氣，形成另類「保護膜」，防止腐蝕向內部延伸。