Natural white stone with grey/black accents. Matte Gold Alloy (mix of various metals). Hypoallergenic. Nickel free. Lead free. Adjustable. One size fits all. Can also be used as a cuff when worn on upper arm. In last photo it's modeled as a bracelet, along with the cut out hook bracelet (another listing). Height of natural stone is 0.3". Offers welcome!