A Solitaire Ring 500/1000 platinum set with brilliant cut diamond with approximate weight of 2.55 ct., N~O colour grade and VVS clarity Portuguese, signs of use Lisbon mark (1938-1984), Carvalho & Castro Ldª makers' mark (1951) Dimensões (altura x comprimento x largura) - 18 cm; Peso - 6 g. Notes: Provenance: Jewelry Collection of a Soprano of the São Carlos National Opera House, Lisbon.