Sterling Silver Ring with Green Royston Turquoise Navajo 16.7g Size 5.75 [7000]. Sterling Silver Ring with Green Royston Turquoise Navajo. The ring has beautiful workmanship surrounded by brilliant silver detail. The ring is a size 5 3/4 The Ring weight is 16.7 Grams with the Royston Turquoise. This ring is not marked and has been tested to sterling. The Sterling Silver Ring with Green Royston Turquoise is in good pre-owned condition. We do our best to describe items as accurately as we can. We sell used vintage items that will likely show normal wear and tear.