Natural Rough Black Tourmaline Black Tourmaline also aids in the removal of negative energies within a person or a space. Black Tourmaline will cleanse, purify, and transform dense energy into a lighter vibration. A popular metaphysical stone, Black Tourmaline is also great for grounding. It balances, harmonizes, and protects all of the Chakras. Black Tourmaline weighs approximately 310 grams Dimensions are approximately 2 3/4 x 2 x 2