PEARI NECKLACE WITH SAPPHIRE INTAGLIO

Description:

PROBABLY ROBERT KOCH, FRANKFURT AROUND 1915-20
L 48 cm
750/000 white gold pendant with a blue sapphire cabochon intaglio approx. 50.00 ct (5.0 x 2.5 cm, probably untreated) and 74 diamond roses totalling approx. 0.35 ct. Pendant is detachable. 77 pearls (probably natural pearls, oval, Ø 3 ⁓ 3.5 mm,) with 24 sapphire spheres (Ø 3.5 ⁓ 4.0 mm). One diamond rose missing and one pearl defect. Original etui. Weight 27.5 g.
Private collection Rhineland, purchased from Koch in Frankfurt and has been in the family for several generations.
Literature:
John Boardman: The Marlborough Gems - Formerly at Blenheim Palace, Oxfordshire, Oxford 2010. For the Apollo gem see No. 118 (Marlborough no. 49).
The master's mark was probably on the original clasp, which was lost. The intaglio shows an Apollo head, probably made after an Apollo intaglio from the 1st century BC that is in the Marlborough Collection.