pitchblende

from WordNet (r) 3.0 (2006)

pitchblende
    n 1: 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 [syn: {uraninite}, {pitchblende}]

from The Collaborative International Dictionary of English v.0.48

Pitchblende \Pitch"blende`\, n. [1st pitch + blende.] (Min.)
   A pitch-black mineral consisting chiefly of the oxide of
   uranium; uraninite. See {Uraninite}.
   [1913 Webster]

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