Design: Simple, contemporary Look: Cross Composition: 925 silver, moissanite 925 Sterling Silver  Work: Shiny Maintenance: Avoid wearing while working out, as sweat can react with the jewelry to create silver chloride and copper sulfide. Imported With: Each moissanite piece over 0.3 carats comes with a certificate of authenticity and a limited warranty card from the gemological research association (gra). A matching case and pouch. Item dimensions: Chain length: 16 inches Additional chain length: 2 inches Gem: 3.6 carats Weight: 0.17 ounces (4.8 grams)