Uranium ores

Uranium ore deposits are economically recoverable concentrations of uranium within the Earth's crust. Uranium is one of the more common elements in the Earth's crust, being 40 times more common than silver and 500 times more common than gold. It can be found almost everywhere in rock, soil, rivers, and oceans. The challenge is to find those areas where the concentrations are adequate to form an economically viable deposit.

Globally, the distribution of uranium ore deposits is widespread on all continents, with the largest deposits found in Australia, Kazakhstan, and Canada. To date, high-grade deposits are only found in the Athabasca Basin region of Canada.

Uranium deposits are generally classified based on host rocks, structural setting, and mineralogy of the deposit. The most widely used classification scheme was developed by the International Atomic Energy Agency (IAEA) and subdivides deposits into 15 categories.

Uranium is a silvery-gray metallic weakly radioactive chemical element. It has the chemical symbol U and atomic number 92. The most common isotopes in natural uranium are ²³⁸U (99.27%) and ²³⁵U (0.72%). All uranium isotopes present in natural uranium are radioactive and fissionable, and ²³⁵U is fissile (will support a neutron-mediated chain reaction). Uranium, thorium, and potassium are the main elements contributing to natural terrestrial radioactivity.

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