METAL: 18k Gold. MEASUREMENTS: Necklace is 17.75" long, pendant drop is 32mm long + 18mm in diameter. GEMSTONES: Light blue, blue and green sapphire. MARKED: Koplewitz, 18. WEIGHT: 16.5 grams.Gemstones have not been graded for color and clarity ,and tested for clarity and color enhancement, unless stated otherwise.