TOUS Ring Mix set of rings in silver vermeil and dark silver with Ø-2-mm spinel. Width: 1.5-2-2.5 mm. Sterling silver plated with 18kt gold with a thickness of 3 to 5 microns and with no other metal between them. (Dark Silver: Sterling silver covered with a layer of ruthenium, a mineral that gives strength and shine.) Production technique: Smelting.