Uranium mining Cornwall. The first deliberate mining of radioactive ores took place in Jáchymov, a silver-mining city in the Czech Republic. Marie Curie used pitchblende ore from Jáchymov to isolate the element radium, a decay product of uranium. Until World War II uranium was mined primarily for its radium content; some carnotite deposits were mined primarily for the vanadium content. Sources for radium, contained in the uranium ore, were sought for use as luminous paint for watch dials and other instruments, as well as for health-related applications, some of which in retrospect were certainly harmful. The byproduct uranium was used mostly as
Marie Curie what Curie recorded in a sentence of her paper, describing how much greater were the activities of pitchblende and chalcolite than uranium itself: "The fact is very remarkable, and leads to the belief that these minerals may contain an element which is much more active than uranium." She later would recall how she felt "a passionate desire to verify this hypothesis as rapidly as possible." On 14 April 1898, the Curies optimistically weighed out a 100-gram sample of pitchblende and ground it with a pestle and mortar. They did not realize at the time that what they were searching for