About Opal Engagement Rings. All our Opal Engagement Rings are available in a choice of gems and precious metals. You can also add your own personal meaning to any of our Opal Engagement Rings, creating a beautiful memory and brilliant reminder. We use only the highest quality materials to craft our Opal Engagement Rings 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 Opal Engagement Rings. The profile, textures, and details of our Opal Engagement Rings 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 Opal Engagement Rings is even more striking when brought to life in the finest precious materials.