Formula: A₂Nb₂(O,OH)₆Z where A is Na, Ca, Sn²⁺, Sr, Pb²⁺, Sb³⁺, Y, U⁴⁺, H₂O or ◻. And Z is OH, F, O, H₂O

Species:

Lustre: Vitreous, Resinous

Member of: Pyrochlore Supergroup

Name: The pyrochlore group gets its name from the generic name pyrochlore which was first introduced by J. J. Berzelius for a cubic mineral found by N.O. Tank in the 1820s in a syenite pegmatite at Stavern (formerly Fredriksvärn), Norway (Wöhler 1826). It is derived from the Greek πΰρ, fire, and χλωρός, green in allusion to the fact that the mineral usually turns green on ignition.

First Recorded Locality: Stavern (Fredriksvärn), Larvik, Vestfold og Telemark – Norway

Nb-dominant members of the Pyrochlore Supergroup.