Sapphire and diamond ring, early 20th century

Of cluster design, set with an oval sapphire within a frame of circular-cut diamonds, size L^1/2.

Sapphire measuring approximately 10.5 x 8.5 x 5.6mm, calculated to weigh approximately 4.20 carats, light violetish blue, typical inclusions visible under magnification, some abrasions to facet edges. Estimate total diamond weight approximately 2.80 - 3.20 carats, estimated colour J-K, estimated clarity SI-I. Scratches to mount consistent with age and wear. In 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."