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[R1-P-10] Mineralogical properties of lautenthalite and wroewolfeite from the Nii mine, Hyogo Prefecture, Japan
Keywords:Lautenthalite, Wroewolfeite, Sulfate, Nii mine
Lautenthalite and wroewolfeite have been found in the dump of the Nii mine, Hyogo Prefecture, Japan. The minerals occur in cracks of quartz containing ore minerals such as chalcopyrite, galena and sphalerite.
Lautenthalite is aggregates of platy crystals up to 0.5 mm in length and 0.1 mm in thick. Lautenthalite is always in overgrowth on wroewolfeite. The mineral is blue-green in color with a vitreous luster. It is monoclinic with unit cell parameters of a = 21.557(6), b = 6.019(1), c = 22.467(5) Å, and β = 108.06(3)°. A WDS analysis yields the empirical formula (based on total cations = 7; water by stoichiometry), (Pb0.97Ca0.06)Σ1.03(Cu3.97Zn0.11Mn0.02)Σ4.10(SO4)1.87(OH)6.52·3H2O.
Wroewolfeite is aggregates of platy crystals up to 1 mm in length and 0.1 mm in thick in association with langite, brochantite, linarite and cerussite. The mineral is blue in color with a vitreous luster. It is monoclinic with unit cell parameters of a = 6.042(8), b = 5.637(6), c = 14.45(2) Å, and β = 93.5(1)°. A WDS analysis yields the empirical formula (based on total cations = 5; water by stoichiometry), (Cu3.94Zn0.04Ca0.02Fe0.01Pb0.01Mn0.01)Σ4.04(SO4)0.96(OH)6.14·2H2O. Optically, the mineral is biaxial (-) with refractive indices α = 1.641(2), β = 1.691(2) and γ = 1.701(2), and 2V (calc.) = 47.0°.
Lautenthalite is aggregates of platy crystals up to 0.5 mm in length and 0.1 mm in thick. Lautenthalite is always in overgrowth on wroewolfeite. The mineral is blue-green in color with a vitreous luster. It is monoclinic with unit cell parameters of a = 21.557(6), b = 6.019(1), c = 22.467(5) Å, and β = 108.06(3)°. A WDS analysis yields the empirical formula (based on total cations = 7; water by stoichiometry), (Pb0.97Ca0.06)Σ1.03(Cu3.97Zn0.11Mn0.02)Σ4.10(SO4)1.87(OH)6.52·3H2O.
Wroewolfeite is aggregates of platy crystals up to 1 mm in length and 0.1 mm in thick in association with langite, brochantite, linarite and cerussite. The mineral is blue in color with a vitreous luster. It is monoclinic with unit cell parameters of a = 6.042(8), b = 5.637(6), c = 14.45(2) Å, and β = 93.5(1)°. A WDS analysis yields the empirical formula (based on total cations = 5; water by stoichiometry), (Cu3.94Zn0.04Ca0.02Fe0.01Pb0.01Mn0.01)Σ4.04(SO4)0.96(OH)6.14·2H2O. Optically, the mineral is biaxial (-) with refractive indices α = 1.641(2), β = 1.691(2) and γ = 1.701(2), and 2V (calc.) = 47.0°.