2, alloy, the largest part of the Swarovski necklace is made of alloy, pay attention to alloy rather than ordinary metal, usually cheaper than silver, but more weighty and very tough.
3, rhodium-plated, some necklaces are rhodium-plated, rhodium-plated is a very rare metal, the color is silvery white, very hard and high melting point, low density, very scratch-resistant. The coating used outside can resist corrosion.