Kapellasite

• Named after Christo Kapellas (1938-2004), collector and mineral dealer of Kamariza, Lavrion, Greece
• Kapellasite is isostructural with Haydeeite [Cu₃Mg(OH)₆Cl₂]
• Kapellasite is a metastable polymorph of Herbertsmithite
• Formula: Cu₃Zn(OH)₆Cl₂
• Space group: P-3m1 (No. 164)
• Crystal system: trigonal
• Crystal class: -3m
• Lattice parameters: a = b = 6.300(1) Å, c =  5.733(1) Å, α = β = 90°, γ = 120°

---

Crystal structure^[1] (click on the pictures to download the VESTA file):

(K. Momma and F. Izumi, “VESTA 3 for three-dimensional visualization of crystal, volumetric and morphology data,” J. Appl. Crystallogr., 44, 1272-1276 (2011).)

• CuO₄ square-planar coordination polygons (blue)
• ZnO₆ distorted octahedra (gray)
• Oxygen (red)
• Chlorine (green)

For a 3D interactive version, see here:

https://skfb.ly/6ZNHM

References:

[1] W. Krause, H.-J. Bernhardt, R.S.W. Braithwaite, U. Kolitsch, R. Pritchard
Kapellasite, Cu₃Zn(OH)₆Cl₂, a new mineral from Lavrion, Greece, and its crystal structure
Mineralogical Magazine, 2006, 70, 329-340
DOI: 10.1180/0026461067030336

Advertisement