Black Tourmaline purifies and transforms dense energies. Brings protection from negative energies. A grounding stone that cleanses and supports the base/root chakra. Prevents psychic attack. Grounds energy. Promotes clear rational thought and a positive attitude. Defends against disease. Provides relief from pain and helps with arthritis. Metaphysical properties are provided for your information and are not meant to replace the advice of a qualified physician or medical practitioner. Due to the nature of this product, color, size, and shape will vary. Quarter is used for size reference.