Heidi Horten's Jewels Expected to Yield Record-Breaking $150MM at Christie's

Billed as the largest and most valuable private collection of jewels ever to come to auction, "The World of Heidi Horten" is expected to fetch more than $150 million at Christie's Geneva in early May.

The auction house is confident that "The World of Heidi Horten" collection will easily eclipse the $100+ million sales totals achieved by "The Elizabeth Taylor Collection" ($115MM, 2011) and the "Maharajas & Mughal Magnificence" auction ($109MM, 2019). Christie's noted that these are the only two jewelry collections in history to achieve more than $100 million.

Christie’s will be offering 700 lots from the Austrian art collector and philanthropist during a series of auctions slated for Luxury Week in Geneva, with a two-part live sale taking place on May 10 and 12, alongside an online sale from May 3 to 15.

Among the highlights of the auction are the stunning 90.38-carat "Briolette of India" diamond necklace, the 25-carat "Sunrise Ruby" and the 362.45-carat carved "Great Mughal Emerald Pendant Necklace."

All of the proceeds from the auction will benefit The Heidi Horten Foundation, established in 2020 to support The Heidi Horten Collection, a museum of modern and contemporary art she founded in Vienna, Austria. Funds will also support medical research, child welfare and other philanthropic activities that she supported for many decades. Horten passed away in June of 2022 at the age of 82.

According to Christie's, Horten was known for her elegance, glamor and fine taste.

"Heidi was a sensitive and passionate collector with a deep appreciation for jewelry," said Max Fawcett, head of jewelry at Christie’s in Geneva. "She had a discerning eye and curated a sophisticated collection featuring some of the finest jewels ever to come to market."

She and her husband, Helmut, collected fine works of art and jewels of exceptional quality and rarity. As a wedding gift, Helmut presented his wife with the "Wittelsbach Blue," a natural greyish-blue diamond of 35.56 carats that had formerly been part of both the Austrian and Bavarian crown jewels.

After Helmut's passing in 1987, Heidi continued to refine her jewelry and art collections.

"What makes this collection particularly remarkable is the breadth and quality of the gemstones represented," added Fawcett. "You’ll find everything from costume jewelry and one-of-a-kind haute joaillerie pieces to historic jewels with exceptional provenance."

All eyes will be on these featured lots at Christie's Geneva in May:

The 90.38-carat ‘Briolette of India’ diamond necklace (shown above). According to jewelry historian Hans Nadelhoffer, the stone was cut into its distinctive shape in Paris and sold to Cartier in the early 20th century. In 1950, the stone was purchased by Harry Winston, who made it the centerpiece of a marquise- and pear-shaped diamond necklace. (Estimate on request).

"The Sunrise Ruby" and diamond ring, featuring a 25-carat pigeon-blood, cushion-cut ruby of exception purity. By Cartier. (Estimate $15 million to $20 million).

A three-strand necklace incorporating 175 natural saltwater pearls and highlighted by an 11-carat cushion-shaped pink diamond clasp. By Harry Winston. (Estimate $7 million to $10 million).

"The Great Mughal Emerald Pendant Necklace" featuring a 362.45-carat carved emerald. By Harry Winston. (Estimate $500,000 to $700,000).

A diamond, sapphire and emerald necklace set with a 46.56-carat round brilliant-cut diamond at its center. By Bulgari. (Estimate on request).

Credits: Jewelry images courtesy of Christie's. Heidi Horten image courtesy of The Heidi Horten Foundation.

Skygazers in Australia Treated to Solar Eclipse Featuring 'Diamond Ring Effect'

About 20,000 skygazers descended on the small resort town of Exmouth on Western Australia’s North West Cape last Thursday to experience a wondrous celestial phenomenon — a total solar eclipse that looked remarkably like a diamond ring.

The Diamond Ring Effect, which was first explained by Francis Baily in 1836, occurs when the Moon completely masks out the Sun during a solar eclipse. Due to the rugged lunar landscape, the black outline of the moon is not smooth. Tiny beads of sunlight can still shine through in some places and not in others as the moon slowly grazes past the sun.

These are called Baily’s Beads. When only one dazzling “bead” remains, momentarily, the view of the eclipse resembles a diamond ring. The ring’s glow is produced by the Sun’s corona remaining dimly visible around the lunar silhouette.

The Diamond Ring Effect can be seen in the instant just before the total solar eclipse and in the moment just after. In Australia, the Diamond Ring was visible for only a second or two, while the eclipse lasted about a minute.

NASA astronomer Henry Throop was one of the thousands cheering the daytime blackout, explaining to an NPR reporter that the experience was "mind blowing."

"I feel so emotional, like I could cry," added Fremantle, Australia, native Julie Copson.

Solar eclipses are the result of an uncanny mathematical coincidence. The Moon is 400 times smaller than the Sun, but is 400 times closer to the Earth. This results in two celestial discs that are virtually the same size visually.

On occasion, solar eclipses will occur when the Moon, in its elliptical orbit, is near its farthest point from Earth and appears slightly smaller than average. In that case, the halo of the Sun is more prominent and the Diamond Ring Effect doesn't occur. Instead, we are treated to a “ring of fire” solar eclipse — also known as a "wedding band in the sky."

Scientists described this type of eclipse as “annular,” a word derived from “annulus,” which means ring-like object.

While Exmouth (pop. 3,000) had been touted as the best place in Australia to see Thursday's solar eclipse, the spectacular show was also visible in parts of Indonesia and East Timor.

The next total solar eclipse over North America will take place on April 8, 2024. The next annular eclipse over North America is set for October 14, 2023.

The image, above, was captured by NASA at an observatory in Chile in 2019. Thursday's eclipse was live-streamed by NASA, but the videographer was not able to get a clear shot of the Diamond Ring Effect.

Credit: Image by NASA/Goddard/Rebecca Roth NASA Goddard Space Flight Center from Greenbelt, MD, USA, CC BY 2.0, via Wikimedia Commons.

Storm Mountain Recovers 108-Carat Pink Diamond at Its Kao Mine in Lesotho

Storm Mountain's Kao mine in the Kingdom of Lesotho is quickly establishing itself as one of the world's most important producers of exceptional pink diamonds. Last week, the mining company unveiled a spectacular 108.39-carat fancy intense pink diamond, which ranks among the largest in history.

The yet-to-be-named gemstone is more than twice the carat weight of the mine's previous record holder: the 47.81-carat “Pink Eternity,” which was discovered in 2022. Other notable pink diamonds from the Kao mine include the “Pink Palesa” (21.68 carat, 2021) and the Rose of Kao (29.59 carats, 2018).

The 170.2-carat Lulo Rose, which was discovered in August 2022 by Lucapa Diamond Co. at its Lulo alluvial mine in Angola, is said to be the largest pink diamond recovered in the past 300 years.

Storm Mountain described its newest headliner as a Type IIa gemstone, which is chemically pure with no traces of nitrogen or boron impurities. This type of stone accounts for fewer than 2% of all natural diamonds.

Its color rating of "fancy intense" is one grade below the highest possible grade of "fancy vivid." For fancy-colored diamonds, the general rule is "the stronger the hue, the more valuable the stone." It's still not clear what size and shape of stone will emerge during the cutting process.

Pink diamonds are in high demand and short supply since the November 2020 closure of Rio Tinto’s Argyle mine, which had been the world’s primary source of high-quality pink diamonds.

Storm Mountain Diamonds is jointly owned by Namakwa Diamonds Limited and the Government of Lesotho. According to mining.com, the Kao mine is one of the largest diamond mines in Lesotho and produces about 400,000 carats annually.

All eyes will be on another pink diamond on June 8. The cushion cut, 10.57-carat "Eternal Pink" with a color grade of “fancy vivid” is expected to eclipse $35 million when it hits the auction block at Sotheby’s New York.

The “CTF Pink Star” still holds the price record for any gem sold at auction. The 59.6-carat pink diamond sold at Sotheby’s Hong Kong for $71.2 million in 2017.

Credits: Images courtesy of Storm Mountain Diamonds.