Formula: UTi2O6 or (U,Ca,Th,Y)(Ti, Fe)2O6 Mohs scale hardness: 4,5 - 5,5
Specific gravity: 5,2 g/cm3
Rare earth elements: Y
Other constituents, %: U, Th, Ti
Mineralklasse: Oxide
Uses: a major ore of uranium and radium, a source of helium and as a mineral specimen
It is highly radioactive (U)
Brannerite is a highly radioactive and interesting mineral.
Brannerite is found in the same settings as gold, including placers, quartz veins, and in granite pematities. It may be black, but is more often found in shades of yellow to brown to green. It forms only tiny crystals, which
may be vitreous. Thin sections are translucent, transmitting a yellow-green light. It may fluoresce yellow under short-wave ultra-violet light.It is one end of a series called the Brannerite-Thorutite series.Associated Minerals include gold.Other Characteristics: radioactive, fluorescent yellowNotable Occurences include Ontario, Canada; Colorado, Stanley Basin, Wyoming, and Custer County, Idaho, USA (the type locality).References
https://en.wikipedia.org
http://www.galleries.com/Brannerite
http://www.mindat.org/min-754.html