Brannerite - Encyclopedia

    Class : Oxides and hydroxides
    Subclass : Oxides
    Crystal system : Monoclinic
    Chemistry : (U,Ca,Y,Ce)(Ti,Fe)₂O₆
    Rarity : Uncommon

Brannerite is a mineral discovered in the Idaho placers. Uranium is strongly oxidized there in the form of U⁶⁺, and frequently replaced by calcium (more than 3% of CaO), thorium (13% of ThO₂), cerium (7% of Ce₂O₃), and yttrium (6.5% Y₂O₃). Its name was given to it in honor of Casper Branner, professor of geology and president of Stanford University. It is found in granitic pegmatites and in certain hydrothermal veins as well as in the alluvial deposits associated with them (Blind River, Ontario, Canada). It is a frequently metamict mineral of variable hue, black to yellow-brown, sometimes black-greenish or yellow-orange. The crystals are elongated, orthorhombic, often flattened on {010}. It sometimes constitutes a uranium ore, especially in alluvium.

Main photo : Brannerite from Power Station, Sportgastein, Austria © Stephan Wolfsried

No twin known for this mineral species.

No fake inventories for this mineral species.