About Birthstone Promise Ring Sets. All our Birthstone Promise Ring Sets are available in a choice of gems and precious metals. You can also add your own personal meaning to any of our Birthstone Promise Ring Sets, creating a beautiful memory and brilliant reminder. We use only the highest quality materials to craft our Birthstone Promise Ring Sets with meticulous attention to detail. Our precious metals are recycled or responsibly mined. We hand-select each conflict-free gem in to perfectly complement your selection from our Birthstone Promise Ring Sets. The profile, textures, and details of our Birthstone Promise Ring Sets add individuality and style to everything you wear. When our work is done and you open that box, you'll see your design from our Birthstone Promise Ring Sets is even more striking when brought to life in the finest precious materials.