The two naturally occurring radioactive ores are Uranium ore and Thorium ore. Other radioactive elements (for example Radium) are found as small impurities in Uranium and Thorium ores. Generally speaking, Uranium ores are more radioactive than Thorium ores. An interesting fact is that 98% of the radiation emitted from Uranium ore is actually coming from the tiny (<0.01%) Radium impurity in the ore - which is why Uranium ore is more radioactive than Uranium metal. Ore availability varies throughout the year.
How Ore is Measured
The radiation measurements stated on all of our radioactive items is guaranteed to be accurate. All samples are measured with a modern, calibrated Geiger Counter as well as a calibrated Stabilized Assay Meter. We measure the total Beta and Gamma radiation emissions from each sample in CPM (Counts Per Minute) using a standard 'Hot Dog' probe (such as a Ludlum 44-6). For our Uranium Ore Samples, we have introduced Alpha/Beta/Gamma readings using a more sensitive 'Pancake' probe (such as a Ludlum 44-9). All of our Uranium Ore samples will come with two side-by-side 'hot dog' probe and 'pancake' probe readings.
See our Radiation Measurement Page for more information.
Where do we search for ore?
Ore Radiation Level & Grading Chart
Cloud Chamber Source
Uranium Ore Radiation Range 'F' (12,500 to 15,000 CPM)