Antipinite

IMA formula: KNa₃Cu₂(C₂O₄)₄

Crystallography: Triclinic. P-1. a = 7.1574(5) Å, b = 10.7099(8) Å, c = 11.1320(8) Å, α = 113.093(1) °, β = 101.294(1) °, γ = 90.335(1) °.

Specimen #6. Antipinite. Pabellón de Pica, Chanabaya, Iquique, Iquique Province, Tarapacá, Chile. FOV 3.2 mm.

Antipinite is a very rare organic copper mineral. It was found in only 2 localities in the world: Rowley Mine, Arizona, USA and Pabellón de Pica, Iqueque, Tarapacá, Chile. The antipinite from Rowley Mine comes from bat guano, while the one from Pabellón de Pica comes from sea bird (probably guanay cormorant) guano.