Kiryuite and gunmaite, two new minerals from Tsukubara, Kiryu City, Gunma Prefecture, Japan

Kiryuite and gunmaite were found as new minerals from Tsukubara, Kiryu City, Gunma Prefecture, Japan. is a Mn-rich analogue of viitaniemiite with an ideal formula NaMnAl(PO4)F3 that mainly occurs white powder in cracks triplite aggregate, occasionally forms porous plate-like aggregates up to 5 mm size, while the grains are several micrometers size. In most cases, also accompanied by small amounts other such goyazite, gorceixite, fluorite. shows streaks vitreous luster, its Mohs hardness estimated be analogy viitaniemiite. The calculated density 3.32 g·cm-3 based on empirical unit cell volume refined X-ray diffraction (XRD) data. for kiryuite basis O = 4 F + OH 3 Na0.97(Mn0.56Ca0.38Fe0.04Mg0.02)Σ1.00Al0.98P1.02O4(F2.29OH0.71)Σ3. monoclinic (P21/m) 5.425(4) Å, b 7.128(4) c 6.817(6) β 109.41(7)°, V 248.7(3) Å3 (Z 2). parameters [d Å (I/I0) hkl] six strongest lines associated XRD pattern 3.123 (57) 002, 2.923 (53) 012 120, 2.877 (100) 121, 2.560 (27) 200, 2.263 (43) 103, 2.155 (76) 221. Gunmaite alunite-related mineral structure type has (Na2Sr)Sr2Al10(PO4)4F14(OH)12. core hexagonal tablet crystals coexist gorceixite goyazite-like minerals. colorless transparent greasy resinous luster non-fluorescent. As bulk crystal including gunmaite, 5, cleavage perfect {001} planes, tenacity brittle. 3.38 using single-crystal 16 26 (Na1.72Sr0.70Mg0.56Ca0.01)Σ2.99(Sr1.32Ba0.68)Σ2(Al9.82Mg0.18)Σ10P3.99O16F16.21(OH)9.79. trigonal (R3m) 6.9972(2) 50.270(2) 2131.51(13) 3). consists two PO4, AlO2(OH)4, AlF6, AlOF3(OH)2, SrO6(OH)6, NaF8 polyhedra. products final stage hydrothermal activity association greisenization.