Thorium 232 primer

2019 video gives a good primer .

“THORIUM 232 – From History to Reactor

This is a visual summary of all the information about thorium.
Thorium is a weak radioactive element with atomic number 90 and a half-life of 14.05 billion years. About the age of the universe. Although it is one of the rarest metals on earth, its availability is much higher and stable than that of Uranium. 99.98% of this element is encountered as thorium 232 while uranium is mostly found in as Uranium 238 which is a poor contributor for the production of energy.

Uranium reserves are estimated to be about 5.5 million tones but only 0.72% of that is U235 necessary for the reaction. In comparison, thorium reserves are estimated to be 6.3 million tones with a 99.98% usability.