14k White Gold 6mm Round Aquamarine 4-Prong Studs Amazon Curated Collection. $130.00. It's not easy to find an earring that is suitable for all of your activities But the White Gold Round Cut Birthstone Stud Earrings are ideal for a casual day or a thrilling night on the town. Made in China. This piece uses an ear-nut back for easy on/off. Save 55%!