J.C. REVY, ISM / SCIENCE PHOTO LIBRARY J.C. REVY, ISM / SCIENCE PHOTO LIBRARY
A sample of black uraninite (uranium oxide) and yellowish-brown gummite (uranium hydroxide). Dense black crystals of uraninite are occasionally found, but it usually occurs in lustrous, black masses (as here), when it is known as pitchblende. Uraninite is highly radioactive and forms an important source of uranium for the nuclear industry. It also provides radium, used as a radiation source in various branches of industry and medicine. It was in a sample of pitchblende obtained from Joachimstal in Czechoslovakia that Marie and Pierre Curie first identified the radioactive elements polonium and radium.
Model release not required. Property release not required.