From: Preguica Mine, Sobral da Adiça, Moura, Beja, Portugal.
  
Cluster of small transparent, white or yellowish, submillimetric prismatic crystals with a vitreous luster of Willemite on a Limonite matrix (ochre colour). Mineralisation of a supergene enrichment zone of a zinc and lead deposit with the formation of a gossan rich in carbonates, phosphates and Zn/Pb silicates. Sample measuring 4.2 x 2.5 x 1.7cm .