Where is Uranium Found?
Uranium occurs in a variety of different geological environments; in igneous, hydrothermal and sedimentary settings. There are 14 major categories of uranium deposits defined by these settings. This article covers only the four major environments from which the majority of western world supply originates. Over 33% of the world’s uranium resources are in unconformity-related deposits such as the Athabasca and Thelon Basins, Canada and the Pine Creek Geosyncline (Alligator River deposits), and Rudall River Areas in Australia. Hydrothermal breccia iron-oxide-hosted deposits (IOCG) such as Olympic Dam in Australia account for approximately 30% of world uranium resources, sandstone (roll-front) deposits such as found in the Western Cordillera of the United States constitute over 18% of world uranium resources and paleoplacer (quartz-pebble conglomerate) deposits such as those at Elliot Lake, Ontario and Witwatersrand in South Africa constitute approximately 13% of world uranium resources. T
• Uranium, known as the heaviest naturally occurring element, can be found in soil and rock, in rivers and oceans, in a variety of different geological environments. • Concentrated uranium ores are commonly found in hard rock or sandstone and vary according to the substances mixed with and where it was originally found. • Uranium deposits can be found all over the world. Larger areas include Australia and Canada. • High-grade deposits are only found in Canada. • Kazakhstan, Niger, Russia and Namibia follow close behind in production, and combined with Canada and Australia, they account for about 84% of production from mines. • McArthur River in Canada (Cameco), Ranger in Australia (ERA) and Olympic Dam in Australia (BHP-Billiton) are the three largest operations in the world by annual uranium production. Mining Uranium Uranium is extracted from the ground using a variety of different mining techniques, depending on the depth of the mineralization and grade. • Open Pit When found close
Uranium deposits are found all over the globe. The world’s largest deposits are found in Canada (25% of global reserves), Australia (19%), and Kazakhstan (13%). With Saskatchewan containing the largest concentration of actively mined uranium reserves, and two additional mines coming within the next decade, Canada is poised to provide about half of the world’s uranium supplies.
Uranium is a naturally occurring element that has the highest atomic weight (~238 g/mole) and is slightly radioactive. It can be found in minute quantities in most rocks, soils and waters (normally < 5 ppm), but the real challenge is to find it in high enough concentrations to make it economically feasible to mine. Uranium is easily oxidized and forms a number of common uranium oxides and oxy-hydroxide like uraninite (or pitchblende) and schoepite (including meta- and para-). Uranium can be found in soils and waters due to the breakdown (weathering) of rocks containing it. Once it is in the soil and water, it can be taken up by plants and consumed by people or grazing animals, or it can dissolve in the water to be consumed by any organism.
Uranium is one of the most abundant elements found in the Earth’s crust. It can be found almost everywhere in soil and rock, in rivers and oceans. Traces of uranium are even found in food and human tissue. However, concentrated uranium ores are found in just a few places, usually in hard rock or sandstone. The concentration of uranium varies according to the substances it is mixed with and the places where it is found. For example, when uranium is mixed with granite that covers 60% of the Earth’s crust, there are approximately four parts of uranium per million, i.e. 999,996 parts of granite and four parts of uranium.
