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

[R1P-07] Johannite from the Kenzan district, Okayama prefecture, Japan

*Takefumi Niwa¹, Tatsuya Kubozono², Seiichiro Uehara³ (1. Min. Soc. Nagoya, 2. Fukuoka Min. Club, 3. Kyushu Univ. Museum)

Keywords:Johannite, Kenzan

In the Kenzan district of Okayama prefecture, uranium ore had been explored. Johannite(Cu(UO₂)₂(SO₄)₂･8H₂O) from this district was found in a sample stored in the Okayama university. Johannite is a grass-green aggregate found in the cracks of granite. Qualitative analysis with EDS yielded results consistent with its ideal chemical formula. The results of X-ray diffraction are in good agreement with the ICDD PDF #01-076-6179. The unit cell parameters were obtained as triclinic cell: a = 8.907(6), b = 9.505(4), c = 6.808(7)Å, α = 109.9(0), β = 111.9(9), γ = 100.3(5), V = 470.3(6)ų.