One interesting thing I learned recently is that pre-1945 steel[1] sells at a high premium because all modern steel has been noticeably contaminated by atomic testing. This has lead to large-scale illegal salvaging of old warship wrecks[2].

1: https://en.wikipedia.org/wiki/Low-background_steel 2: https://www.outsideonline.com/2168646/how-does-entire-shipwr...