Cabochon Opal Stud Earrings in 14k Yellow GoldCabochon Opal Stud Earrings in 14k Yellow Gold. These lovely opal and diamond earrings are a perfect splash of color and shine in a dainty stud earring package. Made in 14 karat yellow gold, these studs hold the oval shaped opals with small round brilliant cut diamonds sitting atop one end. The opals have a nice flashes of color and bring a prismatic quality that works with any outfit.