R1: Characterization and description of minerals (Joint Session with The Gemmological Society of Japan)

[R1P-07] Whewellite from Ishidera, Wazuka, Kyoto Prefecture, Japan

*Yohei Shirose¹, Kenji Tsuruta², Norimasa Shimobayashi³ (1. Grad. Sch., Ehime Univ., 2. Kyoto City Univ. Arts., 3. Grad. Sch., Kyoto Univ.)

Keywords:whewellite, weddellite, oxalates, hydrothermal alteration, Ishidera

Whewellite was found in quartz vein from Ishidera, Wazuka, Kyoto Prefecture, Japan. This is first discovery of whewellite in Japan. Whewellite occurs on altered fluorapatite with weddellite and crandallite-florencite. The average chemical composition is (Ca_0.97Fe_0.01Al_0.01) (C₂O₄)_0.99(PO₄)_0.01·0.94H₂O. The unit cell parameters are a = 6.288(7), b = 14.57(1), c = 10.097(8) Å, β = 109.37(9)°, V = 873(1) ų. The oxalates were formed after a dissolution of fluorapatite.