Watercolors by Effy Collection's nautical-themed starfish pendant necklace features round-cut diamonds with a vibrant mix of round, oval and pear-cut ceylon, orange sapphire, tsavorite and yellow sapphire, as well as oval and pear-cut green sapphire, pear and round-cut pink sapphire and round-cut purple sapphire and red sapphire. Metal: 14K Gold Metal Color: Yellow Stone: Multi Shape Multi Sapphire 5.43 Stone 2: Round Diamond 0.28 Pendant Diameter: 1" 23" Chain Included. I tested it and it is a low karat of gold (5-10k), possibly plated. Not sure what the hallmark means but I included a photo. Effy Watercolors 14K Yellow Gold Multi Sapphire & Diamond Pendant, 5.71 TCW pre-owned in excellent condition