Gadolinite-(Ce) from Skien, southwestern Oslo region, Norway

Cerium-rich gadolinite containing the larger REE occurs in a syenite pegmatite near Skien, Norway. It shows REE zoning with a rim rich in Ce and poor in Y (25 weight percentCezOs;2 weight percent Y,OB), relative to the core (15 weight percent CezOr; l4 weight percent YrO3). X-ray studies how that the unit cell is slightly larger than for gadolinites-(Y). The chondrite-normalized REE pattern of the gadolinite-(Ce) shows strong enrichment of the larger REE relative to the smaller REE. This is believed to be related to the larvikite-derived pegmatit ic l iquids; it is not believed to have resulted through leaching of the basaltic ountry rock