Tags: Chemical Substance, Mineral.
Fergusonite is a mineral comprising a complex oxide of various rare earth elements. The chemical formula of fergusonite species is (YRE)NbO4 where RE = rare-earth elements in solid solution with Y. Yttrium is usually dominant (the species fergusonite-(Y)) but sometimes Ce or Nd may predominate in molar proportion (species fergusonite-(Ce) and fergusonite-(Nd)). All the other rare earth elements are present in subordinate amount and tantalum substitutes for some of the niobium.
