The NPR.org news article and podcast Greenland Is Not For Sale. But It Has The Rare Earth Minerals America Wants is interesting, and it includes a few large GIFs (too large to post here) that appear to show a UV light being waved over some rocks (not really in the dark) and bright red spots lighting up indicating the presence of some mineral containing a rare Earth element.
Compounds containing rare Earth's including oxides have strong transitions in the visible and infrared and some will fluoresce with visible light. When you read what I type over the internet the signal has probably been amplified dozens of times by erbium-doped silica fiber optic amplifiers at the bottom of the ocean (and everywhere else) and those are likely pumped by Nd:YAG lasers (neodymium-doped yttrium aluminum garnet).
But are UV lights really able to so easily find rare Earth-containing rocks on the ground in Iceland, or are these GIFs slightly gratuitous?
Question: Can I just walk around Greenland with a UV light and find rare Earth minerals on the ground?