Measurement instructions: All bracelets are made in size ranges. Please measure your wrist and choose the size range closest to your size before adding the item to your cart. For an exact measurement, use a measuring tape. Make sure the measuring tape is firm around the base of your hand. Alternatively, you can use a string or strip of paper. Wrap it around your wrist, and use this length to measure against a ruler. Sizes displayed are in inches. Natural properties of the stones in this bracelet: Black Onyx: This is a powerful protection stone that absorbs and transforms negative energy. It helps to prevent the drain of personal energy and it aids in the development of emotional and physical strength and stamina. Malachite: Balance, abundance, manifestation and intention. Cleanses energy, known as the stone of transformation. Lava stones: Grounding, for strength and courage, calming, and these rocks can be used as a personal essential oil diffuser. Simply add a drop or two of your favorite essential oil on the lava rock and rub it over the beads.