I believe the main radioactive material we mine for are Uranium and possibly Thorium. Which have very long half lives.
Most other radioactive materials you hear about are created in nuclear reactors or other facilities for various purposes. They usually only have a half-life of a few years, sometimes even less. There are some medical isotopes that have half lives measured in hours or less. So they isotopes must be made almost [immediately before use](https://www.youtube.com/watch?v=eMTZvA8iFgI).
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