For the first time in the Far East features of composition, genesis and evolution of pyrochlore in ongonite and zwitter are established and described. The parity of mineral composing elements allows to allocate three rare pyrochlore species formed consistently: bismutopyrochlore and uranpyrochlore in ongonite, plumbopyrochlore in zwitter. Are established typomorphic features of pyrochlore. All three species of pyrochlore are formed by multiphasic metasomatic replacement of earlier accessories. At transition from late-magmatic to greisen stages of development of Verhneurmijsky ore knot there is a decrease in concentration Ta, increase of mineral composing roles Nb, W, U, Y and chalcophylic elements.
Keywords: pyrochlore group, bismutopyrochlore, uranpyrochlore, plumbopyrochlore, ongonite, zwitter, Verkhneurmiysky tin ore knot, Amur river region.