About a week before the original “Rare and Precious” was scheduled to post, I received my hardcopy of my monthly IEEE Spectrum. It took me a few days thereafter to read through this issue until I saw the paper version of the source article for this paper.
I knew right away that this covered similar ground to the original “Rare and Precious.” The subject was the same: the search for critical (rare and precious) elements.
These posts complement each other by covering different parts of, and different methods for this search.