Pearl necklace with interchangeable clasp,

Pearl necklace with interchangable clasp, 42 cultured pearls, D: 9 - 9.5 mm, white, good lustre, 20 intermediate parts with totalling 120 single cut diamonds, totalling ca. 0.6 ct, clasp with 67 brilliant cut diamonds, totalling ca. 2.4 ct, good colour and clarity, centerstone ca. 1.0 ct, WHITE(H)/SI, 18K white gold, 76.9 g, L: 44 cm late 20th century, minimal signs of wear.