From the latter quarter 20th century, these are a pair of openwork dome amethyst French screw back earrings. The earrings are made in 18 kt yellow gold while the French screw backs are 14 kt. The earrings feature 2 round brilliant cut amethysts that weigh about 3.0 cts total weight.
Hallmark: 18BI (earrings); 14KT / 8062B (French backs)
Overall diameter: About 17 mm
They sit up about 3/16"
Weight: About 8.3 grams
18kt YELLOW GOLD Pair of Openwork Dome AMETHYST French Screw Back Earrings B0171