TOUS Costura ring in silver vermeil with blue sapphire, yellow sapphire, tsavorite and ruby. Width: 11.4 mm. Sterling silver plated with 18kt gold with a thickness of 3 to 5 microns and with no other metal between them. Production technique: Casting. Quality Certificate: 925 sterling silver plated with 18kt gold. To ensure your TOUS jewelry always sparkles like new, we offer a free cleaning and maintenance service for all our jewelry.