“ 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.”
“ A rich southern landowner once imported hundreds of thousands of spiders and distributed them along his long, tree-lined road. After a couple of days, when the spiders had make an incredible number of webs amongst the rows of trees, he spread fine gold and silver dust on them to create a spectacular shimmering view. (true story) It was for his daughter's wedding day.”
“ There is a land where every person wears spectacles. Those without eyeglasses are considered to be the lowest stratum of society, so adventurers without glasses are treated like outcastes. It certainly would explain those heroes wearing sunglasses for no apparent reason...”