Black Obsidian is a powerful cleanser of psychic smog created within your aura, and is a strong psychic protection stone. This stone has powerful metaphysical properties that will help to shield you against negativity. The energy of these stones may stimulate the gift of prophesy and may boost precognition. Obsidian is truth-enhancing. A strongly protective stone, it forms a shield against negativity. It blocks psychic attack and absorbs negative energies from the environment. Obsidian draws out mental stress and tension.