Location: Neves-Corvo Mine, Castro Verde, Beja, Portugal.
Cluster of tabular grayish-green crystals up to 3-4mm, transparent and with vitreous lustre. Sample with 4.0 x 3.5 x 1.5cm. Formed in a marine volcano-sedimentary environment of Paleozoic age and associated with one of the largest copper deposits in Europe.