Lot 2073. The Aurora Green. A superb 5.03 carats rectangular-cut fancy vivid green diamond ring. Estimate HK$125,000,000 – HK$155,000,000 ($16,000,000-20,000,000). Photo Christie's Image Ltd 2016.

Set with a rectangular-cut fancy vivid green diamond, weighing approximately 5.03 carats, within a circular-cut pink diamond surround, extending to the shoulders, mounted in gold, ring size 6

Accompanied by a monograph and a report no. 2206954168 dated 20 January 2016 from the GIA Gemological Institute of America stating that the diamond is fancy vivid green colour, VS2 clarity; also accompanied by a letter from GIA stating that the diamond is the largest Fancy Vivid Green, Natural Color, diamond GIA has graded as of 20 January 2016

Notes: 

The Aurora Green. Photo Christie's Image Ltd 2016. 

Coloured diamonds are a natural phenomenon. The geological conditions required to yield these exceptional gemstones are rare, making diamonds with distinct colours of pink, blue, red and green unique and valuable. The colours are commonly acquired by the addition of a certain element, such as boron for blues and nitrogen for yellows. However, in the case of green diamonds, the colour is acquired through radiation. On the occurrence that a diamond deposit lies near radioactive rocks, the radiation displaces carbon atoms from their normal positions in the crystal structure, causing absorption in the red region of the colour spectrum, thus producing a green colour. Green diamonds frequently contain a yellowish, brownish or greyish modifying colour with a light tone, hence pure green diamonds are highly sought after and the value escalated by the intensity of the saturation. The vast majority of naturally coloured green diamonds only maintains their colour on the surface and is generally forgone after cutting, contributing to the rarity of green diamonds.

Perhaps the most famous green diamond is the Dresden Green. Weighing approximately 41 carats, the diamond is named after Dresden, the capital of Saxony, Germany. Acquired by Augustus II of Poland from a Dutch merchant in 1741 at the Leipzig Fair, the pear-shaped diamond was incorporated into a hat ornament in 1768. Graded by the GIA in 1988, the diamond was determined to be fancy green colour. However, more significantly, the Dresden Green was examined to determine a test to differentiate between naturally green diamonds and lab-produced green diamonds. Lab-produced green diamonds are irradiated by neutron or electron bombardment to create a color center. Because of the possibility of such treatment, green diamonds are examined meticulously at the GIA to determine natural origin.

Presented in the following lot is The Aurora Green. Graded by the GIA, it is the largest, natural fancy vivid green diamond in the world the prior was 3.88 carats). Named after the natural phenomenon ‘Aurora borealis’ or ‘Aurora australis’, the diamond’s saturated colour and scintillation is emulated by the magical display of dancing lights that can only be seen above the magnetic poles of the northern and southern hemispheres. The auroral display appear in a spectrum of colours, however vibrant vivid greens cascading through the sky are the most anticipated and admired. Indeed, it is only this natural marvel that can befittingly describe the natural wonder that is The Aurora Green.

REFERENCE: Kane, Robert E., Shane F. McClure and Joachim Menzhausen. “The Legendary Dresden Green Diamond.” Gems & Gemology 1991: 248-266. Print.

Christie's. HONG KONG MAGNIFICENT JEWELS, 31 May 2016, Convention Hall