Black diamond and diamond ring

Collet set with an oval black diamond weighing 58.85 carats, to a mount pavé-set with brilliant-cut black diamonds and diamonds of near colourless tints, British hallmarks, size O.

Accompanied by Gem-A report no. 0128301 stating that the black diamond is natural, with no evidence of treatment. British hallmarks for 18 carat gold, Birmingham, 2008. Maker's mark PJS. Black diamond stated to weigh 58.85 carats. Estimated total weight of diamonds of near colourless tint approximately 3.00 - 5.00 carats, estimated colour I-K, estimated clarity VS on average. Remaining black diamonds in good condition. Scratches to mount consistent with 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."

Accompanied by Gem-A report no. 0128301, stating that the black diamond is natural, with no evidence of treatment.

Black diamonds are traditionally known as “Carbonado” from the Portuguese word for “burned”. The colour which can come in various shades from grey, blue, brown or black is normally the result of submicroscopic platelets composed of graphite and carbon which gives these unusual stones a metallic lustre. More intriguing is recent scientific research that has proposed that the origin of black diamonds may have originated from an asteroid that impacted with the Earth during the Archean Eon. Unlike diamonds found formed under the Earth’s surface under tremendous heat and pressure, black diamonds are found in alluvial deposits in South America and contain gasses suggestive of cosmic origins.