Euchroite

IMA formula: Cu₂(AsO₄)(OH)(H₂O)₃

Crystallography: Orthorhombic. P2₁2₁2₁. a = 10.056(2) Å, b = 10.506(2) Å, c = 6.103(2) Å. Z = 4.

Specimen #246. Euchroite. (Mystery Mine,) Monte Cristo Mining District, Snohomish County, Washington, USA. FOV 6.3 mm.