Wraithbone
From LSWiki
Wikipedia describes the source inspiration of this material here. Wraithbone in Lost Souls is a sturdy, lightweight mineral with psychic properties.
Phase: Solid Typical Color: Opalescent Rarity: Exotic Properties: Mineral, Psychic, Stone and Sturdy
Development Information: The wraithbone material was created by Chaos, who wishes to credit Games Workshop as inspiring this work; the source code was last updated Wed Jan 31 04:34:11 2007.