The full-day sourcing and networking event, slated for Aug. 18, will be followed by the 5th Annual Mega Mixer Summer Soirée.
Buyers Went Crazy for Hester Diamond’s Mineral Collection
Every lot was sold at the Sotheby’s auction, with 98 percent topping their highest pre-sale estimates.

Diamond was a prominent New York interior designer and philanthropist (and mother of Beastie Boy “Mike D”).
She got her start at an antiques gallery before she and her first husband, Harold, became enmeshed in the fine art world and built up quite a collection of their own.
After Harold’s death, Hester began to sell of much of the modern art she had collected to focus on the Old Masters, a passion that blossomed with her second husband, Ralph Kaminsky.
She was also interested in minerals, collecting specimens with aesthetics that appealed to her, and interior design.
Her passion for interior design was reflected in the way she displayed everything in her home, contrasting Old Masters with contemporary furniture and displaying her minerals on colorful, custom-made shelves.
Diamond died in January 2020 at the age of 91.

Last week, her art collection and her mineral collection went up for sale in a single-owner auction at Sotheby’s.
The auction house confirmed to National Jeweler that all 126 minerals featured in “Fearless: The Collection of Hester Diamond Part II” sold.
The mineral collection totaled $1.5 million, more than tripling its highest estimate of $358,450. Sotheby’s said 98 percent of the auction’s lots sold for more than expected.
The top lot was a Colombian emerald specimen from the Coscuez mine in Boyacá (seen at the top of the article).
It was estimated to sell for between $3000 and $5,000, but ended up garnering $81,900 at the auction.
An azurite with malachite from the Bisbee Mine in Arizona, sold for $52,920, compared with a pre-sale high of $12,000; an anhydrite from Mexico garnered $50,400, compared with a $600-$800 pre-sale range; and a rhodochrosite from the storied Sweet Home Mine in Colorado estimated to sell for $8,000-$12,000 ended up going for $44,100.
A pyrite specimen from Spain, for example, had 16 bidders going after it, and 16 were also going for a hemimorphite specimen from China, while 15 chased after quartz from Arkansas.
Visit Sothebys.com to see all results.
The top lot was a rare sculpture by Gian Lorenzo Bernini and his father, called “Autumn,” which sold for $8.9 million.
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