R1: Characterization and description of minerals

[R1-13] Nevadaite from Ishidera, Wazuka, Kyoto Prefecture, Japan

*Yohei Shirose¹, Satomi Enju³, Kenji Tsuruta⁴, Norimasa Shimobayashi² (1. Kyoto Uni. Mus., 2. Kyoto Uni. Sci., 3. Ritsumeikan Uni., 4. Kyoto City Univ. Arts.)

Keywords:Nevadaite, phosphate, unknown mineral, hydrothermal alteration, Ishidera

Nevadaite was discovered from quartz veins in the Ishidera area, Wazuka, Kyoto Prefecture, Japan. This is the first discovery of nevadaite in Japan. In XRD experiments, the unit cell parameters of nevadaite are a = 12.152(4) Å, b = 19.068(7) Å, c = 4.964(2) Å, V = 1150.1(5) ų. The chemical composition of nevadaite by EPMA analyses is (Cu_3.06Vacancy_2.94)Al_7.96(PO₄)_4.00[PO₃(OH)]_4.00[F_4.95(OH)_3.05)](OH)₂·16.41(H₂O). Nevadaite from the Ishidera area has a vanadium-free composition, and Al and vanadium in M sites of nevadaite is substituted by Cu and vacancy.