Euchlorine (KNaCu3(SO4)3O) is a rare emerald-green sulfate mineral found naturally occurring as a sublimate in fumaroles around volcanic eruptions. It was first discovered in fumaroles of the 1868 eruption at Mount Vesuvius in Campania, Italy by Arcangelo Scacchi. The name 'euchlorine' comes from the Greek word εΰχλωρος meaning "pale green" in reference to the mineral's color, other reported spellings include euclorina, euchlorin, and euchlorite.