3.0 x 2.0 x 1.5 cm. Quite uncommon, fluor-elbaite has been found only a few places around the world. The crystals in this cluster are deep blue-green, with great luster and excellent terminations. The fluor-elbaites are gemmy to translucent, and the parallel growth of the crystals gives the specimen a very architectural look. This piece is considered among the best of species for this tourmaline variety (per Jim Houran, comments). A very fine specimen. Ex. James (Jim) Houran Collection. From: Arqueana pegmatite, Piauí valley, Taquaral, Itinga, Minas Gerais, Brazil. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Fluor-elbaite
Fluor-elbaite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃F.
It crystallizes in the hexagonal crystal system (space group R3m). It is a member of the Tourmaline structural group.
Key properties: Mohs hardness 7.5; White streak; Vitreous luster; optically uniaxial.
IMA symbol Felb, IMA status: approved, named in 2011.
Formed in or near miarolitic cavities by late-stage hydrothermal solutions in a zoned granitic pegmatite.
It is found associated with Quartz, muscovite, lepidolite, spodumene, spessartine, beryl.
As an elbaite with dominant fluorine in the W site.