A metal is a material characterized by metallic bonding and electronic states that permit substantial electrical conduction. Many metals also conduct heat well and can deform plastically through motion of crystal dislocations. These are typical behaviors rather than a claim that every metal has identical hardness or appearance.
For example, copper is a useful electrical conductor, while mercury is liquid near room temperature. A protective oxide can make a reactive metal resist further corrosion. The word can denote either an elemental chemical classification or a metallic material such as an alloy, so composition and structure should be specified.
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