Hambergite on Albite
Sahatany Valley, Sahatany pegmatite field, Antananarivo Province, Madagascar
Thumbnail, 2.7 x 2.6 x 1.3 cm
A rare matrix specimen showcasing a gemmy, prismatic 2.8cm crystal of hambergite perched on an albite shard. A sharp, transparent to translucent (at the base) crystal with well developed prism faces and a good termination! You rarely see matrix specimens of Malagasy hambergites and the faces on this one have a silky to vitreous luster depending on orientation. Hambergite, a beryllium borate, is a rare accessory mineral in granite pegmatites.