For that, you need something like this gamma-ray spectroscope. Dubbed the Pomelo by [mihai.cuciuc], the detector is a homebrew solid-state scintillation counter made from a thallium-doped cesium ...
A gamma ray detector on a device developed by a Cornish company is being used to assess soil quality. Farmer Malcolm Barrett, a tenant farmer from St Tudy near Bodmin, is working with scientists ...