fluoborite

{{Infobox mineral | name = Fluoborite | category = Borate mineral | boxwidth = | boxbgcolor = | image = Fluoborite.jpg | imagesize = | caption = Fluoborite found in Italy | formula = Mg3(BO3)(F,OH)3 | IMAsymbol = Fbo | strunz = 6.AB.50 | system = Hexagonal | class = Dipyramidal (6/m) H-M symbol: (6/m) | symmetry = P63/m | unit cell = a = 8.8612, c = 3.1021 [Å]; Z = 3 | molweight = 186.61 g/mol | color = Colorless to violet or white | habit = Acicular, prismatic, stellate | twinning = | cleavage = Good on {0001} | fracture = | tenacity = | mohs = 3.5 | luster = Vitreous to silky | refractive = nω = 1.570 nε = 1.534 | opticalprop = Uniaxial (−) | birefringence = 0.036 | pleochroism = | streak = white | gravity = 2.98 | density = | fluorescence = Intense cream-white under SW UV | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Translucent to transparent | other = | references = }} Fluoborite has a chemical formula of Mg3(BO3)(F,OH)3. Its name comes from its main chemical components, fluorine and boron. It was first described in 1926.

Fluoborite's crystal system is hexagonal, meaning it has one six-fold axis of rotation. It also has a mirror plane perpendicular to the c-axis. Fluoborite is uniaxial, just like all other hexagonal minerals. Uniaxial means it has only one optic axis. It is anisotropic. Its relief is low, and it is birefringent.