Allanite-(Ce) - (Ce,Y,Ca)₂(Fe²⁺,Fe³⁺)Al₂(SiO₄)(Si₂O₇)(O)(OH)

Habit: Light brown to black. Crystals tabular to long prismatic; can be granular as well; often metamict. Resinous to submetallic luster; translucent to opaque. Weakly radioactive. Grayish brown streak.

Environment: A common accessory mineral in many igneous rocks, especially felsic and metamorphosed igneous rocks. Also occurs in pegmatites, skarns and tactites.

Etymology: Named for Thomas Allan (1777-1833), the Scottish mineralogist who first observed the mineral.