Hydroxylherderite (twins) (ex Rolando Gioia Collection)

Item Description

An unusual specimen of grey-green colored Hydroxylherderite from an undisclosed locality in Brazil. The piece feaures a pair of fine quality, sharp, well-formed "fishtail"-twinned crystals measuring up to 1.7 cm long, but the underside of the specimen shows a rare association of Pyrite, which is not common in pegmatite localities in Brazil. A bit of bladed white Albite can be seen as well, and the piece has excellent form, aesthetics and quality. No damage on the display side, and only a small separation on the back of the bigger crystal where it separate from the pocket wall. Very attractive and a worthwhile pickup for anybody who collects this kind of material. From the collection of Rolando Gioia (a contributor to new definitive book on Brazilian minerals: "Minerais e Pedras Preciosas do Brasil").