Drei-Weg Ring ?Henry Moore?

Ring ?Henry Moore?, 1966 (Bronze Maquette im British Museum loaned from the H.M. Foundation ohne Stein) Ø ca. 15.5/48
GB, 18 Kt. Gold, massiv, Sternsaphircabochon, Stempel kaum lesbar, https://catalogue.henry-moore.org/objects/14036, unclear whether authorized?
Höhe ca. 3 cm, Breite ca. 2.5 cm, Gewicht ca. 74 g