I’m sure I read $60 trillion but I could only find $10 trillion, which is still a huge number:
North Korea is sitting on $10 trillion mineral resources that it can’t tap
https://www.indoasiancommodities.com/2017/09/18/north-korea-sitting-10-trillion-mineral-resources-cant-tap/
Before we allow $10 to $60 trillion of trade with North Korea, Kim Jong-un needs to vanish.
I’ve read that $5-10 trillion estimate, too. It comes from a wildly optimistic South Korean mining company that wants to compete with the national mining company there. The draw is that ROK has to import so much of what they could get cheap from the Norks, particularly iron ore, steel-quality coal, and rare earths. However, all the reserves have been graded by the Norks only, with the exception of ores found during the Japanese occupation. Only with such a high estimate could the Norks convince the ROK, Russians and Chinese to pay for virtually total infrastructure development.