Australia's Thorium Reserves - Resources
Large thorium resources are found in Australia, Brazil, Canada, Greenland (Denmark), India, South Africa, and the United States.
The primary sources of the world’s thorium are the rare-earth and thorium phosphate mineral monazite deposits. In the United States, thorium has been a byproduct of refining monazite for its rare-earth content.
Monazite itself is recovered as a byproduct of processing heavy-mineral sands for titanium and zirconium minerals. 2011 USGS
Australia can be seen to have a large part to play in the coming Thorium supply demand as shown by the USGS and the IAEA tables presented below. There seems to be some opacity in the methods by which the amounts of thorium reserves have been calculated and after several weeks of searching I have been unable to clarify how these figures for Australia were derived.
The prevailing estimate of the economically available thorium reserves by the:
US Geological Survey, Mineral Commodity Summaries (1996–2010)
The IAEA 2005 Estimate
In all probability India has the world's largest resource, with Australia having the second or third largest resource.
In Australia, a larger proportion of the known thorium resources are located in placers where the heavy mineral sand deposits account for about 80% of the known thorium resources. The reason for more thorium resources being reported in the placers in Australia is probably due to the greater amount of data being generated by the active heavy mineral sand mining industry in Australia compared to the lack of analyses for thorium of the other types of deposits. Even for deposits where thorium resources have been assessed, the results have not been well publicised since thorium is not considered to have economic significance. Read more