Uranium mining in Australia Uranium mining in Australia Radioactive ores were first extracted at Radium Hill in 1906, and Mount Painter in South Australia in the 1930s, to recover radium for medical use. Several hundred kilograms of uranium were also produced. Of the world's proven estimated uranium reserves (5,404,000 tonnes), 31% are held in Australia (1,673,000 tonnes), ahead of the second largest, Kazakhstan (12.1% or 651,800 tonnes). In terms of production, Canada is the largest supplier to export markets, followed by Kazakhstan and Australia. Uranium mined in Australia is mainly for export. Australia exported 50,235 tonnes of uranium oxide concentrate in the five years
Uranium ore similar to those in Canada. It is possible that very high grade deposits occur in the sandstones above the unconformity in the Alligator Rivers/Arnhem Land area. Sandstone deposits are contained within medium to coarse-grained sandstones deposited in a continental fluvial or marginal marine sedimentary environment. Impermeable shale or mudstone units are interbedded in the sedimentary sequence and often occur immediately above and below the mineralised horizon. Uranium is mobile under oxidising conditions and precipitates under reducing conditions, and thus the presence of a reducing environment is essential for the formation of uranium deposits in sandstone. Primary mineralization consists of pitchblende