Minimalist Round Australian Doublet Opal Stud Earrings 18k Yellow Gold. Free Domestic USPS First Class Shipping!  Free One Year Limited Warranty!  Free Gift Bag or Box with every order! Opal—the queen of gemstones, is one of the most beautiful and rarest gemstones on earth.  Every piece of opals has its colors and patterns, which is perfect for designers to create unique engagement rings for someone extra special.  We use 100% Natural & Ethically opal stones (NO synthetics or imitations) for our jewelry. --------------------------------------------------------------- ABOUT THIS PRODUCT Solid 18k Yellow Gold Australian Doublet Opal: 0.38 ct Metal Color: Golden Opal Color: Blue, Green Style: Stud, Push Back Opal Measures: 4 x 4 mm