What is Kapellasite?
Kapellasite is a rare copper-zinc hydroxychloride with green micaceous crystals, a layered structure and a famous locality at Lavrion, Greece.
Mineralogy and crystal structure
Reference formula: Cu3Zn(OH)6Cl2. Kapellasite has a trigonal layered hydroxychloride structure related to herbertsmithite and clinoatacamite. Its softness and copper-zinc chemistry make the fine micaceous habit more diagnostic than colour alone. Kapellasite is classified with halides and has a trigonal crystal system. Typical hardness is 2–3 on the Mohs scale and specific gravity is approximately 3.5–3.7.
Colour, lustre and habit
Typical colours include green, blue-green, dark green, black. The usual tabular, micaceous, crusty habit and vitreous, pearly, dull lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Kapellasite forms in or is associated with oxidised copper-zinc deposits and hydrothermal alteration zones. Important documented localities include Lavrion in Greece, the Czech Republic, Spain and other copper districts.
Layered green texture for a modern mineral cabinet
Kapellasite is especially attractive in thumbnail or micro-mount form, where green plates and a contrasting matrix show the layered character clearly. Its Lavrion connection adds a strong locality identity to a compact specimen.
Collecting and care
Soft and fragile: protect micaceous plates from abrasion and avoid acids or prolonged handling.
