U & Th Mineral Collecting Basics



Radioactive minerals are an incredibly interesting, and often misunderstood aspect of the hobby of mineral collecting. When many people hear the word “radioactive”, they tend to panic with images of atomic weapons, or Chernobyl coming to mind. But the reality is quite different. We are surrounded by radiation in our ever day lives. It seeps up from the ground from minute amounts of Uranium that occur naturally just about everywhere. It comes down from outer space from the Sun and sources farther out in the universe. Radiation is everywhere.

Radioactive minerals, also known as U & Th minerals for the primary elements that make them radioactive being Uranium & Thorium have always been a bit of a fringe in the mineral collecting hobby. But with the cost of Geiger counters being so low, and public interest in radioactivity growing, they are quickly gaining in popularity.

If you are still unsure if you want to include some radioactive species in your collection, that’s ok! With a few minor precautions to minimize the already minimal risks, it is quite easy to pursue this part of the hobby.

Specimen Handling & Storage

Handle specimens as little as possible. Wearing gloves is also a good idea. Make sure to wash your hands really well after handling any specimens and do not eat, drink or smoke anywhere near your radioactive mineral specimens.

Store your specimens in closed containers. They do not have to be airtight, but just something to keep the dust off them and out of the hands of curious people, pets and children. Store away from areas where you eat, sleep and spend a lot of time. Clearly mark your specimens as being radioactive. It’s not a good idea to store a large number of specimens in a poorly ventilated area due to the buildup of radon gas. Instead of going after a large examples of the species you are after, consider getting micromount and thumbnail specimens instead. Not only are they more manageable, but also can be many times less expensive than a specimen larger in size.

Useful Equipment


Geiger counters and scintillators are the most useful pieces of equipment to get when collecting radioactive mineral specimens. If you only intend to get a few examples, and only want something to check if something is radioactive, then any of the GQ-GMC series of Geiger counters that you can find on Amazon would be sufficient. If you’re getting more serious about collecting radioactive specimens, then something like a Mazur Instruments PRM-9000, GQ-GMC 600, SE International Ranger or Ranger EXP is what you would be looking for.

If you intend to do any field collecting, than a scintillator is what you would want to be looking for. These are sensitive to Gamma and some betas, but are essential for finding buried specimens. While typically more expensive than Geiger counters, you can still find decent units on eBay or the used market. Keep an eye out for Ludlums, Eberline ASP-1 or ASP-2 and the like. You’ll of course need a scintillation probe to go along with these survey meters. The Rad Lab has some great units at affordable prices.

A UV or Ultraviolet light is another extremely use piece of equipment. While not all radioactive minerals glow, the ones that do tend to do so quite strongly and under all wavelengths of UV light, with some responding to different wavelengths better. Autunite is a great example of this, with some specimens really glowing a quite bright green colour, while Andersonite is more of a teal. These are also useful for cleanup of any pieces that may of flaked off. Longwave flashlights (365nm) can be had for quite cheap off sites like Amazon. Make sure to grab one with a filter. Midwave (310nm) & Shortwave (255nm) are also extremely useful.