1) Mikimoto pearl necklace, each pearl measuring 5.5-6 mm D, with a single 3.6 mm D pearl atop the clasp, maker's mark stamped on the sterling silver clasp, 17 in. L, 2) 14K yellow gold graduated pearl necklace, pearls measuring from 3.2-7.2 mm, with a rosette clasp of a single pearl and halo of round cut diamonds, safety chain, 19 in. L, and 3)14K white gold graduated pearl necklace, pearls measuring from 3.6-7.5 mm, with a circular clasp featuring a single pearl and halo of diamonds, safety chain, 16 in. L, 48.70 grams tw

Comments added on 1/17/2023: The pearls in image #3 is approximately 7.5mm at the center and graduating to 3.65mm at the back