Bavenite Locality: Venero 1 Quarry, Cadalso de los Vidrios, Madrid, Spain (Locality at mindat.org) Picture width 4 mm. Collection Matteo Chinellato, photograph — Photo: Christian Rewitzer · CC BY-SA 3.0
Bavenite
A calcium-beryllium aluminosilicate named for its type locality at Baveno, Italy.
Intro adapted from Wikipedia (CC BY-SA).
Bavenite is an IMA-recognized mineral species in the silicate class, with the chemical formula Ca₄Be₂₊ₓAl₂₋ₓSi₉O₂₆₋ₓ(OH)₂₊ₓ (x = 0 to 1).
It crystallizes in the orthorhombic crystal system (space group Cmcm).
Key properties: Mohs hardness 5.5; specific gravity 2.71–2.74; typically white or colorless or green or pink; white streak; Vitreous luster; optically biaxial.
IMA symbol Bvn, IMA status: approved, named in 1901.
Occurs as druses in miarolitic cavities in granite and associated pegmatites, produced through alteration of beryl and other beryllium-bearing minerals. Also in hydrothermal veins and skarns.
It is found associated with Beryl, helvite, phenakite, bertrandite, quartz, epidote, stilbite, albite, orthoclase, titanite, chlorite, clinozoisite, tremolite.
The name refers to the original occurrence at Baveno, Italy.
Collections: Collector Favorites, Rare & Remarkable.