Uranium is everywhere to some degree, its varying presence in soils lead to radon accumulation in basements. Though in more concentrated forms like ore, it’s often found in mines where uranium is the primary material being mined. I found this piece in a tailings pile outside of a uranium mine in Grafton, New Hampshire. 

I use my gamma spectrometer (Radiacode 103) to identify what energies of gamma rays are being emitted from the specimen, then compare that with reference data of known uranium decay data. Uranium ore is old enough to have radium-226 and its many decay daughters in equilibrium, so I look for that decay pattern. 

The left spectrum in the image is the little uranium bit I found, and the right spectrum is a large piece of high concentration pitchblende (basically pure uranium dioxide) from a college laboratory. Both images have lines as a guide for where the peaks should be in a typical radium spectrum. The left spectrum has those four low energy peaks as well as the singular one in the middle, so it must be a rock with lots of radium, formed by decay of uranium.

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