GEOLOGY & PLANETARY SCIENCE A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site pitchblende Also called uraninite, a brown, black, or greenish mineral, the most important source of uranium, radium, and polonium. The composition of pitchblende varies between UO2 and UO2.6; thorium, lead, and helium are also present. Principal deposits are in Zaire, Bohemia, at Great Bear Lake, Canada, and in the Mountain States. Related category    • GEOLOGY AND PLANETARY SCIENCE Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP