Locality: An abandoned mine about 3 km west southwest of the village of Sierra Gorda, northeast of Antofagasta, 2nd region, northern Chile.
Occurrence: In a quartz – feldspar – tourmaline rock. Other associated minerals are: nitratine, montmorillonite, paratacamite, atacamite, gunningite, alunite and natrojarosite.
General appearance: Thin encrustations of tiny crystals (about 30 μm, rarely up to 100 μm).
Physical, chemical and crystallographic properties: Luster: vitreous. Diaphaneity: translucent to transparent. Color: yellowish green to olive green. Streak: yellowish green. Luminescence: nonfluorescent. Hardness: soft. Tenacity: not given. Cleavage: not given....