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Tarnished sodium metal. Chunk of the reactive metallic element sodium (Na). Part of this surface was recently exposed by a knife cut. However, sodium is a soft alkali metal that reacts rapidly with the water and oxygen in the air. This tarnishes exposed surfaces as the oxide and hydroxide form (see C010/9658 for the shiny, newly exposed surface). Sodium is not found in its elemental form in nature, due to it being highly reactive, and is mainly found in deposits of salt (sodium chloride), from which it is obtained by electrolysis.
Model release not required. Property release not required.