Dingdaohengite-(Ce) was found in assemblage with albite, aegirine, ferroferriwinchite, calcite, pyrite and molybdenite in the central part of the syenite pegmatite of the vein № 125 in Vishnevye mountains in the Southern Urals (the second fnding in Russia). The crystals are subisometric, with sides of pinacoidal {100}, {001}, {201}, {20 1}, { 301}, { 203} and rhombic prisms {110}, {111}. Parameters of the monoclinic unit cell: a = 13.59(3) Å, b = 5.779(6) Å, c = 11.113(18) Å, β = 100.42(19)°, V = 858(3)Å3; empirical formula is (Ce1.77la1.34Nd0.26Pr0.06ca0.48Mn0.05Th0.04)Σ4.00(Fe2+0.61Mn0.39) Σ1.00(Ti0.85Fe0.713+Fe0.242+ Mg0.16)Σ1.96(Ti 1.86 Nb 0.14) Σ2.00(Si4O21.99)  

Figures 3. Table 1. References 10.

Key words: dingdaohengite-(Ce), chevkinite group, Vishnevye mountains, Southern Urals.

A.V. Kasatkin,  Fersman Mineralogical Museum RAS, Moscow, anatoly.kasatkin@gmail.com

V.A. Popov, Institute of Mineralogy UB RAS, Miass;

A.M. Kuznetsov, Oktyabrskaya str., 5-337, Chelyabinsk;

F. Nestola, Department of Geosciences, University of Padua, Padova, Italy

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