Hydrated CO3-bearing analog of manganoeudialyte from alkaline pegmatites of the Konder massif, Khabarovsk Kray
Osipov A. S., Antonov A. A., Panikorovskii T. L., Zolotarev A. A. jr.
Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2017. V. 146. N 4. P. 78-93
Chemical composition, crystal structure and physical properties of a hydrated CO3-bearing analog of manganoeudialyte from alkaline pegmatites of the Konder massif, Khabarovsk Kray, Russia, have been studied. Chemical composition corresponds to the empirical formula: N[Na6.94H2O5.13(Y, REE)0.58Pb0.31K0.28Ba0.08]13.32M1[Ca5.09Sr0.89]5.98M2[Ti0.21Mg0.04Al0.02]1.82M3(Si1.16Nb0.47)1.63M4(Si)0.50Z[Zr3.04Hf0.03]3.07(Si3O9)2(Si9O27)2(CO3)0.28X[(H2O)4.45OH0.04Cl0.03]4.52. Infrared spectrum contain the following bands (s — strong band, sh — shoulder): 455s, 475s, 655, 740s, 925s, 977s, 1010s, 1145, 1420sh, 1504, 1650, 2970sh, 3240sh, 3480 cm–1. The crystal structure is refined in the space group R3m, a = 14.243(3), с = 30.371(6) Å, V = 5336(2) Å3, with R1 = 0.065 for 1393 independent reflections (|Fo| > 4F). The deficiency of sodium and chlorine, the presence of lead and barium, as well as a high degree of hydration of the mineral indicate natural ion exchange processes after crystallization, during the stage of hydrothermal alteration of aegirine-albite rocks of the Konder massif.
Key words: eudialyte, manganoeudialyte, Konder massif, crystal structure, IR, albite-aegirine rock.