“ Mining in a certain area turns all exposed skin (maybe just parts that are actively disturbing the chemicals that cause the reaction) of the those doing the mining to a dark blue color. Will wear off taking as many years/days spent in the mine. ... meeting a party of blue-skinned humans armed with pick-axes etc. Strange disease? Demon offspring? Curse? If they meet only one ex-worker, they will very carefully listen to any stories he says, no matter if drunken or insane, or just makes up to get a beer.”
“ In the days of old, before the dominance of humanity, the giants were the supreme rulers of the world and their crafts were considered to be the best. These beings venerated the god of the forge above all others and their swords and armors were the best that could be had even in the days of their decline. A hero seeking a masterwork sword might have to voyage long and hard to find a surviving giant smith or cache of rare and valuable giantcraft weapons.”