Pearl and gold necklace

centered a detachable pendant, set with an oval pearl approximately 14.50mm x 12.5mm, with seven claw-set round brilliant-cut diamonds weighing approximately 0.50 ct, on an Art Nouveau inspired design, attached to a box chain and lobster catch, 18k yellow gold and 9k yellow gold chain, length approximately 40cm, total weight 38.60 grams