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‘Jonker No. 5’ Could Sell for Nearly $4M at Christie’s
The 25.27-carat diamond is one of 13 stones cut from the famous 726-carat Jonker rough, discovered in South Africa in 1934.
The 25.27-carat Jonker No. 5, one of the diamonds cut from a 726-carat rough diamond found in 1934, could sell for as much as $3.6 million in May. (Photo courtesy Christie’s Images Ltd.)
Hong Kong--Christie’s Hong Kong has unveiled two unique pieces for its upcoming Magnificent Jewels auction May 30, one of which has a storied place in diamond history.
In two months, the 25.27-carat Jonker No. 5 will be up for sale, where it is expected to garner between $2.2 million and $3.6 million. The Type IIa stone is D color, VVS2 clarity and rectangular in cut.
The Jonker No. 5 is part of a legendary collection of diamonds that came from the famous 726-carat piece of rough discovered by Jacob Jonker in South Africa in 1934, which was, at the time, the fourth largest gem-quality diamond to be uncovered.
The Diamond Corporation, owned by Sir Ernest Oppenheimer, subsequently bought the rough, which was again purchased by Harry Winston Inc. in 1935, which allowed it to be displayed during the Silver Jubilee Celebrations of the Coronation of King George V and Queen Mary in London as well as at the Museum of Natural History in New York, according to Ian Balfour’s “Famous Diamonds.”
Harry Winston chose Lazare Kaplan to cleave and cut the Jonker, and the company examined it for months before the diamond took the final form of 13 polished pieces, ranging in weight from 3.53 carats at the smallest to 142.90 carats for the largest faceted stone, though this would eventually be reduced to 125.35 carats to give it a greater brilliance. 
Also for sale at the May auction event will be the “Palmette” necklace, created by renowned designer Edmond Chin for the House of Boghossian.
The piece features 11 perfectly matched, no-oil rectangular-cut emeralds, weighing in range from approximately 3.00 carats to 12.34 carats, surrounded by circular-cut emeralds to create a repeating palmette motif with white diamonds of various cuts as spacers.
It is expected to sell for between $3.6 and $5 million.
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