A kind of volcanic glass, black obsidian is a naturally forming but fragile stone prized for its crafting abilities. Since ancient times, man has used this stone to build knives, arrowheads, sculptures, dishes and even mirrors, thanks to its reflective sheen. People still use black obsidian today for knives and even surgical scalpels due to its sharpness being better than the finest high-quality steel. Spiritualists believe it is the stone of grounding, helping us embrace truth and live a more authentic life.