Lot 1842, The Monarch Mirabella 490. Rare Fancy Intense Green Diamond, Pink Diamond and Diamond Ring. Estimate 21,000,000 — 28,000,000 HKD (2,427,688 - 3,236,917 EUR). Photo Sotheby's.

Centring on a heart-shaped fancy intense green diamond weighing 4.90 carats, surrounded by circular-cut diamond and heart-shaped pink diamonds and diamonds, embellished with pink diamond frames, to the diamond and pink diamond-set edge, gallery and bifurcated shoulders, the pink diamonds and diamonds together weighing approximately 1.70 and 1.50 carats respectively, mounted in 18 karat pink and white gold. Ring size: 5¼

Accompanied by GIA report numbered 1162564833, dated 4 September 2014, stating that the 4.90 carat diamond is Fancy Intense Green Colour, SI1 Clarity. Also accompanied by a GIA monograph.

Note: Aside from the colour red, green is by far the rarest body colour found in fancy coloured diamonds. The green colour is caused by millions of years of exposure to a source of natural irradiation in the earth, either among uranium compounds or percolating ground water, which changes its specific absorption of light. The majority of naturally irradiated diamonds show isolated green strains (also known as ‘skins’) that barely penetrate the surface of the crystal and are almost always removed during the cutting process. However, a very small minority are exposed to the irradiation source over an extended period of time and therefore exhibit an even green hue throughout the entire crystal. Among this extremely select group of stones, only a very few have a true green colour without any bluish, greyish or yellowish secondary colours, making them true rarities, as is the case with this heart-shaped diamond.

Historically, the most famous of all green diamonds is the legendary Dresden Green Diamond, a modified pear-shaped bluish apple-green diamond of 41.10 carats. It is believed that the stone was mined in India, bought by Frederick Augustus II (1733-1763), Elector of Saxony and King of Poland, from the Dutch merchant Delles at the Leipzig Fair in 1741 and set by the Court jeweller Dinglinger in a Golden Fleece Order. It was said at the time that the stone was the first of its kind to appear on the European market.

Only a handful of natural green diamonds have been auctioned in the past thirty years, and most of them exhibited either bluish or yellowish modifying hues. This fancy intense green diamond with a pleasing outline, weighing a 4.90 carats which is uncommonly large for a pure green diamond, is representative of an extraordinary group of beautiful and enigmatic gems, and also presents a rare opportunity for collectors to acquire a unique gem.

Sotheby's. Magnificent Jewels & Jadeite, Hong Kong, 05 Apr 2016, 02:00 PM