a method of uranium exploration employs the detection of radon gas decay products to provide an indication of uranium mineralization . a plurality of collectors of similar surface areas are exposed to soil at or from spaced locations on an exploration site for a time sufficient for the decay products to deposit on the collectors and then , within substantially similar periods following the termination of the exposure , alpha particles , beta particles or gamma rays emitted from the collectors are measured and the measurements are compared . the collectors may be exposed to the soil in air spaces in or on the ground or in containers holding soil samples and may be electrically charged .