Clinoatacamita ¿?
Clinoatacamita ¿? is a mineral with formula Cu₂(OH)₃Cl, in the Halogenuros group. This specimen comes from Mina Chuquicamata, Chuquicamata, Antofagasta, Chile and joined the Terrium collection in 2025.
Description
Not antlerite. Cavity lined with tiny, bright green, lustrous crystals forming a continuous drusy coating. Along the lower edge, a few sky-blue spheroidal aggregates, possibly chrysocolla; identification uncertain.
History of this specimen
Bought at the Vigo Mineral Show 2025 from Silvio J. Rodrigues, who was selling it as "antlerite". I said nothing because I acquired it together with piece 249, which was also mislabelled as galena with sphalerite and was in fact a huge calcite crest. Result: 2 out of 2 errors by the same seller, but two very interesting pieces.
About Clinoatacamita ¿?
Secondary formation in the oxidised zone of a large copper system. The first phase, probably clinoatacamite, crystallised over the cavity; later, on it or adjacent to it, spheroidal aggregates of another secondary mineral—possibly chrysocolla—were deposited, typical of supergene environments in arid climates such as Chuquicamata.
About the locality
Chuquicamata is a historic Chilean mine, noted for an oxidised zone rich in secondary copper minerals such as atacamite, brochantite, chrysocolla and clinoatacamite. It produces very good specimens.
Technical data
- Catalogue No.
- 0191
- Composition
- Cu₂(OH)₃Cl
- Name
- Clinoatacamita ¿?
- Group
- Halogenuros
- Category
- Cavella
- Associations
- Crisocola ¿?
- Mine
- Mina Chuquicamata
- District / Municipality
- Chuquicamata
- Province
- Antofagasta
- Country
- Chile
- Size (cm)
- 5 x 3.5 x 3
- Acquired
- 2025
- Ex-collection
- Silvio J. Rodrigues
- Etymology
- From Greek "klino" ("inclination") and "atacamite", referring to its crystal habit distinct from that of atacamite.
- Quality
- Muy buena
- Value trend
- Estable
Related specimens
- Atacamita — Chile
- Brochantita — Chile
- Pachnolita — Dinamarca