10mm Black Onyx with special Sterling Silver clasp. Will fit wrist size up to 6.5". Black onyx crystals can be used for grounding, protection, and self-control, and as a shield against negative energy. It also enhances discipline, allowing more ease in following through on goals and completing tasks. Silver is known to carry the energies of the moon, especially during new moons and full moons. As Silver is reflective, the moon reflects light coming from the sun, and it does the same for whoever wears it. Silver will reflect negativity away from you, which makes it a stone of magical protection and security.