Casting Bones - same as that used by witch doctors.
This powerful magic item was created to augment Alienists, a prestige class in the Tome and Blood.
Circlet of Amplus Ater Iris meaning “Circlet of The Great Dark Messenger” (Amplus - great, important; Ater - dark, malicious; Iris - messenger of the gods. Thought by some to mean Nyarlathotep)
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.