Obruchevite

Obruchevite, also known as Yttropyrochlore-(Y), is a zero-valent-dominant mineral of the pyrochlore group. Its formula can be written as (Na,Ca,Fe,Y,U)₂(Nb,Ti,Ta)₂(O,OH)₇, or (Y,U,Ca)₂Nb₂O₆ (OH), or YNb₂O₆OH.

The name "Yttropyrochlore-(Y)" for this compound was used by Kalita (1957), and Ercit et al. (2003), but it has now become obsolete and will be discarded. The Yttropyrochlore-(Y) as mentioned by Tindle & Breaks (1998) is in fact oxyyttropyrochlore-(Y).