An Etymological Dictionary of Astronomy and Astrophysics

A natural ore consisting mainly of → uranium oxide, U₃O₈, with small amounts of → radium, of which is the principal source. It usually contains some → lead and variable amounts of → thorium and → rare-earth elements.

See also: From Ger. Pechblende, from Pech “pitch” (from its black color) + Blende “a mineral.”