Thick plates of black Allanite to 5mm and 3cm wide. Excellent specimen with black Thorite between the plates of Allanite.
Although rare earth elements are relatively abundant in the Earth's crust, they are rarely concentrated into mineable ore deposits. For instance, cerium ranks around 25th in the lising by abundance in the Earth's crust of all naturally occuring elements. The ores of rare earth elements are mineralogically and chemically complex and commonly radioactive. This specimen contians the rare earth element, cerium. Cerium makes an excellent oxidizer. It is typically used for catalytic converters.
