Kanonerovite, MnNa3P3O1012H2O, first triphosphate mineral (Kazennitsa pegmatite, Middle Urals, Russia)

Abstract

Kanonerovite, MnNa 3 P 3 O 1 0 .12H 2 O [a = 14.71(1) A, b = 9.33(1) A, c = 15.13(2)A, β = 89.8(1)°, V = 2075(3) A 3 , P2 1 /n, Z = 4], is the first described triphosphate mineral. It has been found in the Kazennitsa pegmatite vein, the Alabashka pegmatite field, Middle Urals, Russia. Associated minerals are quartz, albite, microcline, muscovite, topaz, beryl, cassiterite, milarite. Kanonerovite occurs as tiny, snow-white radial-platy aggregates on cassiterite, topaz, quartz and microcline. It is transparent with a white streak and vitreous lustre and does not fluoresce under long- or short-wave ultraviolet light. In transmitted light kanonerovite is colourless, transparent, non-pleochroic; biaxial (-), nearly parallel extinction (α∧c ∼ 0-7°); a = 1.453(2), y = 1.459(2), β and 2V not measured because of the lamellar habit; birefringence is 0.005-0.006. Kanonerovite is brittle, Mohs hardness of 2.5-3; poor {010} cleavage. D m e a s 1.91(2) g/cm 3 , D c a l c 1.90 g/cm 3 . Strongest reflections in the X-ray powder diffraction pattern [d(A) (I), (hkl)]: 10.50(75)(101), 7.36(100)(200), 6.95(90)(111,-111), 3.316(60)(411,-411,-123,321,-321,313), 3.162(50)(214,-214), 2.889(60)(420,124,032,421). Electron-microprobe analysis gives: Na 2 O 14.80, K 2 O 0.05, CaO 0.20, MgO 0.14, MnO 11.20, FeO 0.15, P 2 O 5 35.23, H 2 O(calc.) 36.46, sum 98.23 wt.%. Occurrence of the triphosphate group (P 3 O 1 0 ) in kanonerovite is shown by IR-data and the crystal structure of the synthetic equivalent compound. The mineral is named for Kanonerov Aleksandr Anatol'evich (b. 1955).