| Takedaite | |
|---|---|
| General | |
| Category | Borate |
| Formula (repeating unit) | Ca3B2O6 |
| IMA symbol | Tkd[1] |
| Strunz classification | 6.AA.40 |
| Crystal system | Trigonal |
| Crystal class | 3m |
| Space group | R3c |
| Unit cell | a = 8.638 Å, c = 11.850 Å |
| Identification | |
| Formula mass | 237.85 gm |
| Color | white, pale gray |
| Crystal habit | Granular |
| Cleavage | {110} imperfect |
| Fracture | Brittle |
| Mohs scale hardness | 4.5 |
| Luster | Vitreous |
| Streak | white |
| Density | 3.10 g/cm3 |
| Optical properties | uniaxial negative |
| Refractive index | ω=1.726, ε=1.630 |
| Ultraviolet fluorescence | non-fluorescent |
| Absorption spectra | 4000 to 250cm−1 |
| Solubility | easily soluble in dilute hydrochloric acid |
| References | [2][3][4] |
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.[2]
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b Kusachi, I., Henmi, C., & Kobayashi, S. (1995). Takedaite, a new mineral from Fuka, Okayama Prefecture, Japan. Mineralogical Magazine, 59(396), 549-552. doi:10.1180/minmag.1995.059.396.15
- ^ Takedaite: Mineral information, data and localities. - mindat.org. (n.d.). https://www.mindat.org/min-3872.html
- ^ Barthelmy, D. (n.d.). Takedaite Mineral Data. https://webmineral.com/data/Takedaite.shtml