How rare earth metals rose from obscurity (▻http://cen.acs.org/artic...
▻https://diasp.eu/p/5969727
How rare earth metals rose from obscurity
Hacker News Comments: ▻https://news.ycombinator.com/item?id=15121930
Source: ▻http://cen.acs.org/articles/95/i34/whole-new-world-rare-earths.html