• A reddish-brown phosphate mineral containing rare-earth metals, (Ce, La, Nd, Y, Th)PO<sub>4</sub>, important as a source of cerium and thorium.
  • A phosphate of the cerium metals, usually containing some thorium silicate.
  • A mineral occurring usually in small isolated crystals, -- a phosphate of the cerium metals.
  • any of a range of reddish-brown <xref>minerals</xref> that are mixed <xref>phosphates</xref> of the lighter <xref>rare earth</xref> <xref>elements</xref> <xref>lanthanum</xref>, <xref>cerium</xref>, <xref>praseodymium</xref>, <xref>neodymium</xref>, <xref>promethium</xref>, <xref>samarium</xref>, <xref>europium</xref>, <xref>gadolinium</xref> and <xref>yttrium</xref>
  • a reddish-brown mineral containing rare earth metals; an important source of thorium and cerium
powered by