These earrings are set with bright green onyx and the gemstones are cut cabochon giving them a smooth, rounded surface like a bubble.  
 
Materials: the earrings are gold-plated sterling silver and set with green onyx.
Details:  the earrings have a post and butterfly fixture and the total drop of the earrings is 2.5 cm.  The round cabochon gemstone is 10 mm.  The top ring has a textured finish applied.