Minirals created from the blood of a World Dragon
When a World Dragons sheds blood, the blood becomes a gemstone. The more blood, the bigger the gemstone.
Such stones have been used in rituals to trap the souls of World Dragons, or smaller shards have been used to create The Hollows.
All of these stones can effect those within proximity to them. Each type of dragon they come from has it’s own emotional association:
Red – Anger
Black – Greed
Blue – Dispair