Sterling Silver Cube White Cubic Zirconia Stud Earrings White Cubic Zirconia Diamond Charm Earrings - in Sterling Silver - ::: [ Potential Enhancement Methods: cubic zirconia ] - Synthetic. Some are covered with a product that makes the stone more durable. ::: [ Care and Handling: cubic zirconia ] - Clean with warm soapy water and a soft cloth. ::: ::: ::: [ Care and Handling: diamond ] - Clean with warm soapy water and a soft brush or cloth. :::