pitchblende

A massive variety of the mineral uraninite.

An oxid of uranium, usually occurring in pitchy black masses, rarely in octahedrons. Also pechblend, pechblende, pechurane, uraninite.

It is a black mineral found chiefly in the mines of the Erzgebirge, between Saxony and Bohemia, and until recently known simply as the chief source of oxid of uranium, used in staining glass and painting on porcelain. In it have been found many of the substances which have been observed to present the property of radioactivity.

A pitch-black mineral consisting chiefly of the oxide of uranium; uraninite. See uraninite.

Naturally-occurring uranium oxide, a variety of the mineral uraninite.

a mineral consisting of uranium oxide and trace amounts of radium and thorium and polonium and lead and helium; uraninite in massive form is called pitchblende which is the chief uranium ore