Whether it’s a gift for a birthday or simply an alternative to the standard diamond engagement ring, gemstone rings are a gorgeous and unexpected choice. Costco carries a diverse selection of beautiful gemstone rings, in a kaleidoscope of colors, including purple amethyst, rich sapphires in an array of hues, color-saturated rubies and emeralds, and popular tanzanite. Looking for drama? Choose a breathtaking emerald surrounded by diamonds as a wedding ring? Love to add a splash of color? Try adding a vibrant ruby eternity band to her existing engagement ring. Whatever your choice, you’ll find exactly what you’re looking for on Costco.com.