(BLACK) OBSIDIAN is thought to be a powerful stone that can offer protection against negativity. It is sometimes called "the stone of truth" because it encourages the surfacing of secrets and hidden emotions. Additionally, obsidian is also thought to be a balancing and grounding stone. Traditional Indian belief systems associate obsidian with the root chakra, which governs sexuality and stability. Obsidian is also considered to be particularly useful for those suffering from depression or addiction.