#orthite
- Allanite — A mineral belonging to the epidote group, black, brown, or gray in color, with a resinous or submetallic luster, containing significant percentages of rare-earth elements (cerium, lanthanum, neodymium, yttrium), alongside traces of thorium or uranium, which give it a weakly radioactive nature. It crystallizes in the monoclinic system and occurs as an accessory mineral in igneous (granites, pegmatites) and metamorphic rocks.
- Anorthite — A mineral belonging to the silicate class, representing the pure calcium endmember of the plagioclase feldspar isomorphic series (calcium aluminum silicate). It crystallizes in the triclinic system, features a white, grayish, or reddish color, and is a common structural constituent in basic and ultrabasic igneous rocks (such as gabbros and basalts), as well as in some metamorphic rocks or meteoritic materials.