Rhodium-Plated Sterling Silver Onyx | Jade | Aquamarine and Diamond Accent Pendant Necklace Rhodium-plated sterling silver necklace with oval-shaped Onyx pendant featuring a trio of accenting diamond rounds above stone 18" Sterling Silver Ropw chain with Spring-Ring clasp Due to the natural properties and composition of mined gemstones, pieces may vary slightly in size, shape, weight and color. Onyx is commonly treated and impregnated with polymers to enhance its color and improve its stability. All our diamond suppliers confirm that they comply with the Kimberley Process to ensure that their diamonds are conflict free