An impressive sapphire and diamond ring, by Boucheron. Photo courtesy Bonhams. 

The oval mixed-cut sapphire, weighing 31.26 carats, between triangular-cut diamond shoulders, diamonds approximately 2.30 carats total, signed Boucheron, maker's mark, French assay marks, ring size O½. Estimate £100,000 - 150,000 (€120,000 - 180,000).

Accompanied by a report from Gübelin stating that the sapphire is of Burmese origin, with no indication of heat treatment. Report number 13100141, dated 17 October 2013.

Accompanied by a report from SSEF stating that the sapphire is of Sri Lankan origin, with no evidence of heat treatment. Report number 71531, dated 4 November 2013.

Bonhams. FINE JEWELLERY INCLUDING SELECTED JEWELS FROM THE COLLECTION OF BARBARA TAYLOR BRADFORD. London, New Bond Street. 5 Dec 2013 - www.bonhams.com