HYDRATED CO<sub>3</sub>-BEARING ANALOG OF MANGANOEUDIALYTE FROM ALKALINE PEGMATITES OF THE KONDER MASSIF, KHABAROVSK KRAY
Chemical composition, crystal structure and physical properties of a hydrated CO<sub>3</sub>-bearing analog of manganoeudialyte from alkaline pegmatites of the Konder massif, Khabarovsk Kray, Russia, have been studied. Chemical composition corresponds to the empirical formula: <sup>N</sup>[Na<sub>6.94</sub>H<sub>2</sub>O<sub>5.13</sub>(Y, REE)<sub>0.58</sub>*Pb<sub>0.31</sub>K<sub>0.28</sub>Ba<sub>0.08</sub>]<sub>13.32</sub><sup>M1</sup>[Ca<sub>5.09</sub>Sr<sub>0.89</sub>]<sub>5.98</sub><sup>M2</sup>[Mn<sub>1.52</sub><sup>3+</sup>Ti<sub>0.21</sub> Mg<sub>0.04</sub> Fe<sup>3+</sup><sub>0.03</sub> Al<sub>0.02</sub>]<sub>1.82</sub><sup>M3</sup>(Si<sub>1.16</sub>Nb<sub>0.47</sub>)<sub>1.63</sub><sup>M4</sup>(Si)<sub>0.50</sub>*<sup>Z</sup>[Zr<sub>3.04</sub>Hf<sub>0.03</sub>]<sub>3.07</sub>(Si<sub>3</sub>O<sub>9</sub>)2(Si<sub>9</sub>O<sub>27</sub>)<sub>2</sub>(CO<sub>3</sub>)<sub>0.28</sub><sup>X</sup>[(H<sub>2</sub>O)<sub>4.45</sub>OH<sub>0.04</sub>Cl<sub>0.03</sub>]<sub>4.52</sub>. 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 <sup>1</sup>. The crystal structure is refined in the space group R3m, a = 14.243(3), c = 30.371(6) A, V = 5336(2) A<sup>3</sup>, with R<sub>1</sub> = 0.065 for 1393 independent reflections (|F<sub>o</sub>| > 4<xF). 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.