LovEnter 18K Yellow Gold Plated White Opal Fashion Ring The diameter: 18mm Gemstone: High Quality (Tarnish free) Crystal. Available in many more colors and styles. Click LovEnter above to see more! Best for Every Occasion; Wedding, Party, Gift, Birthday, Anniversary, Christmas, Mother's Day, Prom, Valentines--Arrives in Gift Box Sold exclusively by LovEnter.