bavenite

{{Infobox mineral|boxbgcolor=#cccccc|image=Bavenite2 Cadalso.jpg|caption=Bavenite. Aggregate of lamellar crystals, with pyrite microcrystals on them.Cadalso de los Vidrios (Madrid), Spain. 13 mm|formula=Ca4Be2Al2Si9O26(OH)2|IMAsymbol=Bvn|strunz=9.DF.25|system=Orthorhombic|dana=70.5.3.1|class=Pyramidal H-M Symbol: mm2|symmetry=Am2a|unit cell=2,250.52|color=White, Green, Pink, Brown|cleavage=Perfect on {001} Fair on {100}|fracture=Uneven|mohs=5.5|luster=Vitreous - Pearly|opticalprop=Biaxial (+)|refractive=nα = 1.578 - 1.586 nβ = 1.579 - 1.586 nγ = 1.583 - 1.593|birefringence=0.005 - 0.007|2V=22° - 60°|dispersion=Moderate r < v|fluorescence=None|streak=White|density=2.7|solubility=Unsoluble in acids|diaphaneity=Transparent to translucent}}

Bavenite is a calcium beryllium aluminosilicate, and it is a part of the Bavenite-Bohseite series. Its name originates from its type locality, which is Baveno, Italy. This mineral is approved by the IMA, and got grandfathered, meaning it is still believed to refer to a valid mineral species. It was discovered in 1901 in a pink granite mined in Lago Maggiore. When bavenite was discovered, it was considered as a member of the zeolite series. Later it was removed from the series as unlike zeolites, bavenite loses the water stored in its crystal lattice in a way higher temperature, between 210 and 320 °C. It is a cheap mineral considering its rarity.