The marquise-shaped diamond weighing 9.75 carats, flanked by millegrain shoulders set with circular- and single-cut stones, mounted in platinum,

Stamped Pt 950 for platinum. Please refer to GIA report for further details on the diamond. Small diamonds to the shoulders of matching quality. Overall in good condition, well preserved.
"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."

Provenance:

Estate of the Late Mrs. Simon Guggenheim, Sotheby's New York, November 17, 1971🃏, lot 135.

Simon Guggenheim (1867-1941) was the son of Meyer Guggenheim and  brother of Solomon R. Guggenheim, the noted art collector and founder of the museum bearing his name in New York City. Simon Guggenheim served as a Republican senator from Cꦑolorado from 1907 until 1913. He and his wife Olga were noted philanthropises whᩚᩚᩚᩚᩚᩚ⁤⁤⁤⁤ᩚ⁤⁤⁤⁤ᩚ⁤⁤⁤⁤ᩚ𒀱ᩚᩚᩚo created  the John Simon Guggenheim Memorial  Foundation,  which awards grants to artists and scholars in memory of their son who died at a young age.