Euchroite Locality: Svätodušná Valley, Ľubietová (Libetbánya; Libethen) ore belt, Western Slovenské Rudohorie Mts, Banská Bystrica Region, Slovakia (Locality at — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Euchroite
A vitreous emerald-green hydrated copper arsenate hydroxide crystallizing in the orthorhombic system.
Intro adapted from Wikipedia (CC BY-SA).
Euchroite is an IMA-recognized mineral species in the arsenate class, with the chemical formula Cu₂(AsO₄)(OH)·3H₂O.
It crystallizes in the orthorhombic crystal system (space group P2_12_12_1).
Key properties: Mohs hardness 3.5–4; specific gravity 3.44; typically green; white streak; Vitreous luster; optically biaxial.
IMA symbol Euc, grandfathered status — known before the IMA’s founding, named in 1823.
A very rare mineral found in the oxidized zone of some copper-bearing hydrothermal mineral deposits.
It is found associated with Olivenite (Lubietová, Slovakia); strashimirite, olivenite, azurite, malachite (Zapachitsa deposit, Bulgaria).
Its name comes from the Greek for beautiful color.
Collections: Collector Favorites, Rare & Remarkable.