Centering a "Jubilee" cut (Round Novelty cut) diamond weighing app. 2.17ct. (I color, SI1 clarity), in a six prong filigree mounting set with sixteen Old European cut diamonds weighing app. 0.48ctw., fashioned in platinum. Hartdegen- Newark, NJ. Vintage. Circa 1930. GIA 2155704186. Size 6.25.