Two gem set and diamond rings

One set with a cushion-shaped tanzanite to a mount set with brilliant-cut diamonds, size M; one collet-set with a cabochon tourmaline within a frame of brilliant-cut diamonds, size N, signed Barakat.

Tanzanite ring: estimated total diamond weight approximately 3.00 - 4.00 carats, stones bright and lively. Tanzanite measuring approximately 21.8 x 19.7 x 12.0 mm, calculated to weigh approximately 31.75 carats, as measured in mount, medium purplish blue, loupe clean. Scratches to metal consistent with wear. In good condition. Tourmaline ring: Stamped 750 for 18 carat gold. Signed Barakat. Tourmaline medium pinkish red, with typical inclusions visible to naked eye. Estimated total diamond weight approximately 1.00 - 2.00 carats, estimated colour H-J, estimated clarity VS on average. In very good condition.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Please note that colour, clarity and weight of gemstones are statements of opinion only and not statements of fact by Sotheby's. We do not guarantee, and are not responsible for any certificate from a gemological laboratory that may accompany the property. We do not guarantee that watches are in working order. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue, in particular to the Notice regarding the treatment and condition of gemstones and to the Notice regarding import of Burmese jadeite and rubies into the US.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD "AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."