Raja Bian Stone Gua Sha Hand-crafted Black Obsidian. Highest quality. Black Obsidian Stone 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. The healing property of the Obsidian stone, combined with the gliding actions: Reduces puffiness Removes blockages Reduces inflammation Visibly lifts and contours Smooths fine lines and wrinkles Tones and firms the skin to give a youthful glow