Cleveite, samarskite and fergusonite contain a little more than monazite.
The rare earth metals are found in the minerals gadolinite, samarskite, fergusonite, euxenite and cerite.
It is found in the minerals gadolinite, cerite, samarskite and fergusonite, and is usually obtained from cerite.
CERIUM (symbol Ce, atomic weight 140.25), a metallic chemical element which occurs with the rare earths in the minerals cerite, samarskite, euxenite, monazite, parisite and many yttrium minerals.
The element was discovered in 1880 in the mineral samarskite by C. Marignac (Comptes rendus, 1880, 90, p. 899; Ann.