Allanite
The Century Dictionary and Cyclopedia
noun.
A silicate of cerium and allied metals with aluminium, iron, and calcium. It is isomorphous with epidote.
the GNU version of the Collaborative International Dictionary of English
noun.
A silicate containing a large amount of cerium. It is usually black in color, opaque, and is related to epidote in form and composition.
Wiktionary, Creative Commons Attribution/Share-Alike License
noun.
Any of a group of
silicate
minerals
that are a source of
rare earth metals
.