Boltwood studied this concept of "radioactive series," and found that lead was always present in uranium and thorium ores. He believed that lead must be the final product of the radioactive decay ...

A discovery deep within a cave in Spain has challenged the history of human artistic expression. Researchers have determined that hand stencils in Maltravieso Cave are more than 66,000 years old, ...

This substance can then decay in a fission reaction. The IAEA also said: “Thorium-232 undergoes a series of nuclear reactions, eventually forming uranium-233, a fissile material that can be ...