On December 9, at Sotheby’s new New York home in the Breuer Building, an impressive lineup of diamonds, important colored stones, and signature house creations went on sale — 136 Lots, led by the reappearance of a long-missing piece of diamond history, the Jonker VI.
The Return of Jonker VI
The star of the sale is the Jonker VI — [pronounced Yong-ker] — a 22.85-carat, D-color, VVS1, Type IIa emerald-cut diamond whose whereabouts have been unknown for nearly ninety years.
Originally part of the historic 726-carat rough crystal, discovered in 1934 on the farm of Jacobus Jonker near Pretoria, the rough was purchased by Harry Winston in 1935 and later cleaved and fashioned in New York — the first time a diamond of this magnitude had ever been cut in the United States.
Image Courtesy of Sotheby’s
In 1936, Lazare Kaplan fashioned a suite of twelve diamonds from the Jonker rough — one marquise and eleven emerald cuts — documented in Laurence S. Krashes’ Harry Winston: The Ultimate Jeweler. The stone designated Jonker VI, cut from a 53.95-carat section, emerged as a 24.91-carat emerald cut. Jonkers IV and VI were quietly sold to American clients, with no names ever revealed. From that point forward, Jonker VI essentially vanished from public record.
Now recut to 22.85 carats, and confirmed by GIA — as reported by Sotheby’s — to have originated from the Jonker rough, Jonker VI has re-entered the public sphere for the first time since its creation. For diamond historians, it is a genuinely noteworthy reappearance.
Sotheby’s estimated the diamond at $1–1.5 million, and it met expectations — ultimately achieving just over $2 million including buyer’s premium.
A Serious Showing of Color
Alongside the Jonker, the sale included a curated group of fancy colored diamonds — not just one standout example, but several stones that would headline their own auctions.
First up, a 3.48-carat Fancy Intense Blue (Internally Flawless, modified pear shape), estimated to sell for between $2 and $3 million, sold for $2.55 million.
There’s a very interesting natural pearl necklace, that hosts 59 graduated round to near-round pearls measuring approximately 10.55 to 5.16 mm. But it’s the clasp that grabbed our attention – set with a 3.78-carat Fancy Blue marquise-cut diamond, estimated to sell for around $1 million, sold for $1.27 million.
Sotheby’s also had a 3.27-carat Fancy Vivid Orangy Pink diamond ring, also estimated to sell for around $1 million, sold for $970,000.
Then there’s a 5.23-carat Natural Fancy Intense Green diamond. Natural green diamonds are extremely rare, and often are extremely difficult to identify as natural. This particular diamond is even more interesting in that the clarity grade is based on “patches of color.”
Rounding out our list (but not the complete auction list) is a 12.51-carat Bulgari ring set with a Fancy Vivid Yellow cushion cut diamond. Fantastic saturation of color, it was estimated to sell for between $450,000 and $650,000, but did not sell.
Signed Jewels — A Strong Supporting Cast
Beyond the headline diamonds, the sale features important pieces by JAR, Van Cleef & Arpels, Oscar Heyman, Hemmerle, Bulgari, Paul Flato and others, including the jewelry designer who created Taylor Swift’s engagement ring – Kindred Lubeck.
Cartier: Fancy Vivid Yellows
Sold for $317,000.
Clarity based on Color Patches?
and reflecting on the pavilion facets so you can see them through the table.
Reflections like these are not supposed to affect clarity.
Lot #208 was pulled prior to the auction, but it was a very interesting stone, not just because of its color, but because of its clarity. So here we have a Cut-Cornered Rectangular Mixed Cut, SI2, Fancy Intense Green, Natural Color, weighing 5.23 carats. The Clarity grade of SI2 is based on “patches of color” that are not shown on the diagram. The inclusions list shows Indented Natural, Needle, and Pinpoint.
We contacted GIA to see about this comment, clarity grade based on “patches of color.”
What’s shown in the table area – marked by arrows – are reflections of the irradiation stains near the girdle area most likely on the pavilion side. These are NOT the patches of color the comment is referring to. Instead, according to GIA, on occasion, when there is an inclusion, such as an indented natural, there can be color patches associated with those inclusions. While details of the location of the specific color patches for this stone was not given, we could assume that the indented natural was most likely the location.
Bulgari
Here is the 12.51-carat Bulgari Fancy Vivid Yellow Diamond and Diamond Ring, that did not sell. It was estimated to sell for $450,000 – $650,000 USD.
Accompanied by GIA report no. 5231246384 dated August 22, 2025 stating that the diamond is Fancy Vivid Yellow, Natural color, Internally Flawless.
Also accompanied by an FCRF Rarity Report. (Tap here to find out more information about the FCRF Report.)
Rare 3.27-carat Fancy Vivid Orangy Pink Diamond Ring
Estimated to sell for $800,000 – $1,200,000 USD, the diamond ring sold for $920,750 USD.
Accompanied by GIA report no. 2185695954 dated September 30, 2025 stating that the diamond is Fancy Vivid Orangy Pink, Natural color, VVS1 clarity.
And also accompanied by an FCRF Rarity Report (see above), stating that the diamond is Extremely Rare, with a market entry rate of once every 8 to 12 years.
Unmounted 3.48-carat Fancy Intense Blue Diamond
Estimated to sell for $2,000,000 – 3,000,000 USD, the Fancy Intense Blue sold for $2,551,000 USD.
The pear-shaped Fancy Intense Blue diamond weighing 3.48 carats was accompanied by GIA report no. 5232465410 dated September 17, 2025 stating that the diamond is Fancy Intense Blue, Natural color, Internally Flawless.
Accompanied by an FCRF Rarity Report.
Harry Winston
The historically important ‘Jonker VI’ Diamond Ring, estimated to sell for $1,000,000 – 1,500,000 USD, sold for $2,002,000 USD.
Featuring the emerald-cut diamond weighing 22.85 carats, the Jonker VI is flanked by a pair of tapered baguette diamonds.
Accompanied by GIA report no. 2201544262 dated August 28, 2019 stating that the diamond is D color, VVS1 clarity. Together with a letter from the GIA stating that the diamond has been found to be Type IIa.
Accompanied by an updated GIA report and monograph.
Two Impressive Diamond Necklaces
Each necklace is designed as a line of graduating old mine-cut diamonds in collet settings. The two strands measure approximately 17¼ inches and 15¼ inches in length and can be attached to be worn as a single long necklace, with additional diamond links totaling approximately 4¼ inches.
Estimated to sell for $350,000 – 550,000 USD, the necklaces sold for $825,500 USD
The diamonds, weighing a total of approximately 132.00-134.00 carats, ranging from approximately 4.70 to 0.30 carat, are approximately G-M color, VS-SI clarity with a few I clarity examples.
The additional links are set with 13 old mine-cut diamonds that weigh approximately 8.00 carats total weight.
Kindred Lubeck
Set with a 2.02 elongated cut-cornered rectangular step-cut Fancy Orangy Pink Diamond was estimated to sell for $150,000 – 250,000 USD, sold for $177,800 USD.
Lubeck stepped into the spotlight when she helped American football star Travis Kelce design an engagement ring for pop superstar Taylor Swift.
Accompanied by GIA report no. 5231311974 dated July 17, 2024 stating that the diamond is Fancy Orangy Pink, Natural color, VS1 clarity.
Accompanied by an FCRF Rarity Report.
Van Cleef & Arpels
Here we have a pair of ‘Mystery-Set’ Ruby and Diamond Earclips, Made in France, estimated to sell for $100,000 – $150,000 USD, sold for $241,300 USD.
The bombé style earclips are set with calibré-cut rubies on one side, and pavé-set round diamonds on the other.
Hemmerle
A stunning Copper and Spessartine Garnet Bracelet by Hemmerle, features five cushion-cut medium deep slightly reddish orange spessartine garnets, alternating with rounded rectangular links, the sides of which are set with round spessartine garnets (see above).
Estimated to sell for $80,000 – $120,000 USD, the fantastic bracelet sold for $139,700 USD.
Burmese No-Heat 17-carat Sapphire Ring
Estimated to sell for $70,000 – $100,000 USD, this amazing 17.23-carat Burmese no-heat sapphire ring sold for $279,400 USD.
Accompanied by three gemological reports:
AGL report no. 152203 dated November 12, 2025 stating that the sapphire is of Burmese origin, with no indications of heating.
Gübelin report no. 0909722 dated October 1, 2002 stating that the sapphire is of Burmese origin, with no indications of heating.
GRS report no. GRS2009-090962 dated September 1, 2009 stating that the sapphire is of Burmese origin, with no indications of heating, and that the color may be referred to as ‘Royal Blue.’
Van Cleef & Arpels: Chalcedony and Coral
Here we have a Van Cleef & Arpels Chalcedony, Coral, and Diamond Sautoir, created in France, estimated to sell for $55,000 – $75,000 USD, sold for $171,450 USD
Condition report
18 karat gold
Light orangy pink coral
Medium slightly bluish green and translucent chalcedony
Round diamonds (8.85 carats total weight)
Rose-cut diamonds (2.65 carats total weight) – “of decorative quality.”
Value here is obviously not determined by the sum of its parts.
Bulgari Diamond, Ruby and Emerald Ring
Estimated to sell for $45,000 – $65,000 USD, the ring sold for $165,100 USD.
As you can see, the ring features two Featurinlarge Old Mine Cut diamonds, a pair of cushion-cuts, weighing a total of 6.62 carats.
The ring is then accented by calibré-cut rubies on one side and similarly cut emeralds on the other, accented by pentagon- and trapezoid-shaped diamonds.
Workmanship and design are the standouts here – besides the two Old Mine Cuts, of course.
David Webb – a Little Perspective
Until we saw the necklace on the model, we had no clue that it would be so …. large. Created using Nephrite, Amethyst, Ruby, and Diamond, Webb’s “Demon Mask” Necklace-Brooch Combination was estimated to sell for $20,000 – $30,000 USD. Getting off to a slow start, the auction ended up in a frantic pace, selling for $508,000 USD!
“The detachable clip-brooch designed as a carved nephrite mask of pre-Columbian inspiration wearing a textured gold headdress bezel-set with cabochon amethysts, the eyes similarly set with oval-shaped rubies, accented by round diamonds, suspended from a necklace composed of five rows of graduated amethyst beads, internal circumference approximately 16 inches, signed Webb; circa 1973.“
Interesting note: The total weight of the necklace is approximately 403 dwts.
Van Cleef & Arpels – Wood, Gold, and Diamonds
Last but not least for us here, we have a pair of Gold, Wood and Diamond ‘Clématite’ Earclips, made in France. Estimated to sell for $6,000 – $8,000 USD, the earclips sold for $25,400 USD
“Designed as flowerheads composed of carved wood petals, the gold wire pistils enhanced with round diamonds, signed V.C.A., numbered, with French assay and maker’s marks. With signed box.”
All in all, we have for you an important historic diamond, fancy color diamonds now accompanied by a Fancy Color Research Foundation report, Kindred Lubek, Old Mine Cuts, Vivid Spessartine, a fabulous emerald cut Burmese Sapphire, a HUGE Nephrite necklace, Wood earclips, and some invisible set ruby and diamond earrings…. And there’s more of course…
Tap here to see all of the results at Sotheby’s!
