Question

what turned monazite sand into a higly valuable resource​

Answer 1

3.04.2.1 Thorium as an Abundantly Available Resource for Nuclear Fuel

Thorium is more abundant than uranium: The content of thorium in the earth’s crust is estimated to be about three to four times larger than that of uranium. Its most common source is the rare earth mineral monazite. Monazite sand is found in large amounts in India and Brazil, and Australia has large deposits as well. It should be noted, however, that the exact amount of thorium resources is not very well known. Estimates of thorium resources (identified resources, retrievable at a cost less than USD 80 per kg Th) are given in Table 1, taken from the Uranium Red Book 2009.16 This overview estimates a total of known resources of 2.5 million tons Th (identified resources) and an additional prognosticated amount of 1.9 million tons.

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