A Greek key decorated bar brooch, 19th century

gold, silver (unmarked, approx. 0,750 and 0,800 respectively), 1 round cut faceted sapphire weighing approx. 0,50 ct, 10 rose-cut diamonds weighing in total approx. 0,30 ct H/SI, length: 4 cm, weight: 5,29 g; accompanied by a gemmologist’s certificate