Burbankite Locality: Poços de Caldas , Poços de Caldas plateau, Minas Gerais , Southeast Region, Brazil ( Locality at mindat.org ) Light pink crystal of Burbankite (analysed). Field of view 5 mm. Specimen and photo Leon Hupperichs. — Photo: Leon Hupperichs · CC BY-SA 3.0
Burbankite
Burbankite is an IMA-recognized mineral species in the carbonate class, with the chemical formula (Na,Ca)₃(Sr,Ba,Ce)₃(CO₃)₅.
It crystallizes in the hexagonal crystal system (space group P6_3/mmc). It is a member of the Burbankite structural group.
Key properties: Mohs hardness 3.5–4; specific gravity 3.5–3.58; Vitreous luster; optically uniaxial.
IMA symbol Bbn, grandfathered status — known before the IMA’s founding, named in 1953.
Typically an abundant accessory mineral in carbonatites; in an intrusive alkalic gabbro-syenite complex; may be authigenic.
It is found associated with Ancylite, calkinsite, lanthanite, calcite, “biotite”, barite (Big Sandy Creek, Montana, USA); ancylite, carbocernaite, calcite (Mont Saint-Hilaire, Canada).
The mineral was named to honor Wilbur Sweet Burbank (1898–1975), geologist of the U.S. Geological Survey.