Federally funded remedial action projects are presently underway in New Jersey and Colorado at sites containing 226Ra and other radionuclides from radium-uranium ore extraction plants that operated during the early twentieth century. They are but the latest chapter in the story of an American industry that emerged and perished in the span of three decades. Major extraction plants were established in or near Denver (CO), Pittsburgh (PA), and New York City (NY) to process radium from ore that came largely from the carnotite deposits of western Colorado and eastern Utah. The staffs of these plants included some of the finest chemists and physicists in the nation, and the highly-refined radium products found a variety of uses in medicine and industry. The discovery of high-grade pitchblende ores in the Belgian Congo and the subsequent opening of an extraction plant near Antwerp, Belgium, in 1992, however, created an economic climate that put an end to the American radium industry. The geologic, chemical, and engineering information gathered during this era formed the basis of the uranium industry of the later part of the century, while the tailings and residues came to be viewed as environmental problems during the same period.