Inesite from the Kokuriki Mine, Hokkaido, Japan

概要

論文の詳細を見る
Inesite occurs in veinlet cutting hematite ore from the Kokuriki mine, eastern Hokkaido. Its associated minerals are rhodochrosite, barite and quartz. The inesite forms fine prisms up to 1 mm long and is pale orange in color. Refractive indices are: α=1.618(3), β=1.639(3) and γ=1.656(3). Biaxial, negative. 2V(meas.)=67-70°. The composition is as follows: SiO2 45.94, Al2O3 0.02, Fe2O3 0.57, MnO 37.50, MgO 0.10, CaO 8.60, Na2O 0.04, K2O 0.04, H2O 8.90, Total 101.71 wt.%. The H2O content was determined by a thermogravimetric analysis. The empirical formula is calculated as: (Ca1.97Na0.02K0.01)Σ2.00(Mn6.80Mg0.03) Σ6.83-(Si9.84Fe3+0.09Al0.01)Σ9.94O35.00H12.72. Unit-cell parameters based on morphological cell were determined by X-ray powder diffraction as follows: a=8.938(4), b=9.259(5), c=11.959(5)Å, a=91.96(7)°, β=132.72(3)°, γ=94.36(6)°. Crystal field spectra indicate that the orange color of the inesite may be caused by Mn3+ converted from a part of Mn2+ .
北海道大学 = Hokkaido Universityの論文