Very Attractive Diamond ring

The Old Mine brilliant-cut diamond weighing 6.13 carats, simply mounted in platinum, size 51½.

Stamped Pt950 for platinum. Accompanied by GIA report no. 6127143123 and by Gübelin report no. 1007083, stating that the diamond is D Colour, Internally Flawless. Together with GIA diamond type classification report and Gübelin note stating that the stone is a Type IIa diamond. Further accompanied by Gübelin appendix stating that: Diamonds of this type, exhibiting an antique cutting style as well as superior quality, are very rare and will most certainly evoke references to the historic term of 'Golconda'. Please refer to the GIA report for further information on the diamond. Condition as new.
"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."

'Golconda' is a name steeped in the annals of diamond lore. The name of a now ruined fortress which originally served as a commercial trading centre, some days distant from the historic Indian mines of Ramalakota, Kollur and Soumelpour. The term 'Golconda' has now survived to describe the historic diamonds peculiar to India of great limpidity and purity. These diamonds are from the famed 'First water' mines, which produced the world's most spectacular diamonds, such as The Koh-I-Noor, The Hope and The Agra. This beautiful stone, with its appealing antique cut, is a member of the rare Type IIa group of diamonds known for their extreme purity, qualities compared so often throughout history to pure crystallized water. Scientifically this purity is due to the absence of nitrogen, producing stones often said to be beyond white.

In our opinion, this present gemstone may well be part of the highly desirable group of surviving diamonds which were mined in the Golconda region up to the beginning of the XVIIIth century.