Estate Tiffany & Co Ziegfield Sterling Silver Black Onyx 28 Inch Long Statement Necklace. This elegant necklace is fully engraved: TIFFANY & CO AG 925 on the plate at the clasp. The clasp is engraved: 925. It measures 28 inches long and weighs 21.5 grams. The pendant measures 1.74 inches long X 1.29 inches wide. It comes in its Tiffany box and pouch. Please visit my ebay store for unique estate jewelry. Thank you.