Australian Opal Hoop Earrings in 14k Yellow GoldAustralian opal hoop earrings in 14k yellow gold by The Hileman Collection. These hoop opal earrings feature six sections of opal inlaid in each hoop. The Australian opal in these earrings is a nice mix of blues and greens. These opal earrings measure approximately 5. 3mm at the widest point. They measure 21mm in diameter and come with 14k gold posts and nuts. These earrings can be made in white gold and in other inlay materials by special order.