Elemental Bones are a lethal poison to the majority of the living species, including humans:
- if touched, it would burn the skin
- if it enters the eye, it cause blindness
- if consumed, the innards would be dissolved.
Although they are described to "shine an aquamarine light", they are referred to as [Black ash], since the nature of it symbolises death itself.
During the Great War, humans (Imanity) would wear dust masks and fur armour in order to prevent themselves from coming into contact and inhaling Black ash. Black ash was also used by some of Imanity to conceal their identities by applying it directly onto their bodies in order to disrupt identification magic and the senses of the other races.