takedaite

{{Infobox mineral | name = Takedaite | category = Borate | image = | caption = | formula = Ca3B2O6 | IMAsymbol = Tkd | molweight = 237.85 gm | strunz = 6.AA.40 | system = Trigonal | class = m | symmetry = Rc |unit cell = a = 8.638 Å, c = 11.850 Å | color = white, pale gray | habit = Granular | twinning = | cleavage = {110} imperfect | fracture = Brittle | tenacity = | mohs = 4.5 | luster = Vitreous | polish = | refractive = ω=1.726, ε=1.630 | opticalprop = uniaxial negative | birefringence = | dispersion = | pleochroism = | fluorescence= non-fluorescent | absorption = 4000 to 250cm−1 | streak = white | gravity = | density = 3.10 g/cm3 | melt = | fusibility = | diagnostic = | solubility = easily soluble in dilute hydrochloric acid | diaphaneity = | other = | references = }}

thumb | right Takedaite is a borate mineral that was found in a mine in Fuka, Okayama Prefecture Japan during a mineralogical survey in the year 1994. During the survey, Kusachi and Henmi reported the occurrence of an unidentified anhydrous borate mineral closely associated with nifontovite, olshanskyite, and calcite. By the year 1994 two other minerals in the borate group M3B2O6 had been identified in nature Mg3B2O6 known as kotoite and Mn3B2O6 known as jimboite. Takedaite has the ideal chemical formula of Ca3B2O6. The mineral has been approved by the Commission on New Minerals and Mineral Names, IMA, to be named takedaite after Hiroshi Takeda, a professor at the Mineralogical Institute, University of Tokyo Japan.