Unique Cartier 18 kt 52nd Street Sign Diamond Pendant with Necklace. This is a beautiful piece and is in great condition. It is an 18 kt yellow gold 52nd Street PL. De Cartier diamond pendant with an 18 kt yellow gold Cartier chain necklace. The pendant is 20 mm across and 30 mm from top to bottom. The chain is 16.5 inches long. The chain weighs 6.8 grams, and the pendant weighs 4.2 grams.