Sterling Silver Onyx Inlay Rectangle Pendant Necklace with Beads, 18" Gemstones may have been treated to improve their appearance or durability and may require special care. Use a polishing cloth to clean. Naturally occurring imperfections may be present, adding to the unique beauty of each piece. The natural properties and composition of mined gemstones define the unique beauty of each piece. The image may show slight differences to the actual stone in color and texture.