Necklace with 15 brilliant-cut diamonds totaling ca. 1.69 ct (hallmarked),

Necklace with 15 brilliant-cut diamonds totalling ca. 1.69 ct (marked), ca. WHITE (H)/VS-SI, 1 stone chipped, 18K white gold, 24.6 g, L: 42 cm, with extensions from later times and satinization of surface, 2nd half of 20th century, signs of wear and rework.