Among the Gutman items being auctioned at Sotheby’s were five ornate Jewish marriage rings. At the viewing, Zucker was knocked out by one of these, an 18th-century example topped by a tiny gold house with a hinged gable roof tiled in rich blue enamel. It opened to reveal a plaque engraved with letters standing for  mazel tov, or “good fortune.” “It was one of the most beautiful things I’d ever seen,” he says.

The piece was estimated at $500, and Zucker was determined to have it. Not taking any chances, he cashed in his entire stock portfolio, which was worth $15,000. When the lot came up, he raised his paddle and kept thrashing it in the air until the bidding reached $1,700 and the auctioneer told him he could lower it; he’d won. That day Zucker bought four Jewish marriage rings for a total of $5,300. He was launched as a collector.

Alas, his success in the salesroom wasn’t matched at his writing desk. The novel wasn’t progressing well, and when Charles Zucker asked his son to join him in the business not long after the auction, Benjamin agreed—a failed book was no match for filial piety. Charles also assured Benjamin that he could continue writing (indeed, Zucker has produced several books, both fiction and nonfiction, with jewelry as their theme). Soon Benjamin was studying gemology and accompanying his father on buying trips to the Far East. The skills honed by Zucker the gem merchant proved a great help to Zucker the collector, as he kept an eye out for antique rings to purchase—Greek and Roman, Etruscan, Islamic, Renaissance, Art Deco.  

As with the best Old Master paintings, the number of very fine antique rings for sale has declined since Zucker started buying. “They have become rarer and the prices have gone up, but I still think that these rings are undervalued works of art,” says the collector, who has paid as little as $120 and as much as $200,000 for his treasures, acquired most frequently from the London dealer S. J. Phillips, on Bond Street; the gemologist and jewelry historian Jack Ogden; and Derek Content, a private dealer in ancient jewels. Because the market is small, prices have not skyrocketed and, even at the top, remain relatively reasonable. When Zucker bought his gimmel ring from S. J. Phillips, in 1980, it cost him £10,000 ($23,000). A comparable example today, according to top dealers, including S. J. Phillips, might command from the low five figures to as much as £75,000 ($150,000).

Last year Zucker purchased an 18th-century yellow diamond from the London dealer Sandra Cronan. It has become part of his current project to illustrate the history of gem cutting and the story of Elihu Yale, the American-born British trader and politician who made a fortune dealing in diamonds and used part of it to help fund the university that, in gratitude, took his name. “One of the most exciting moments in my collecting came 10 years ago when I read the biography of Elihu Yale,” recalls Zucker. “The idea that the university I loved was built on a diamond fortune was so interesting.” He also learned that Yale was a prodigious collector of art, objects, textiles and jewels and that after his death, an auction of 10,000 lots was held that lasted 40 days.

Zucker found the man’s life so gripping that he has suggested an exhibition on Elihu Yale, diamond trader, to the university’s art museum and has put together a book proposal on the subject for which he is seeking a publisher. With the future show in mind, he has acquired 20 diamond rings, brooches and necklaces illustrating different styles of cutting. These, plus eight rough sapphires from the Zucker Family Collection, will be displayed at Yale’s Peabody Museum of Natural History when phase two of its Hall of Minerals, Earth and Space opens November 15.

The earliest of the 20 diamond pieces is a 15th-century ring containing a single small, uncut octahedral crystal. “Diamonds were so rare at this time,” says Zucker, taking a last look at the gems in his 47th Street office, on New York’s Diamond Row, before sending them off to New Haven on long-term loan. Another jewel in the group is a pretty 17th-century Dutch table-cut diamond pendant set in yellow gold with delicate pale pink and white enameled flowers on the reverse. The star of the group, though, is the 5.8-carat yellow hobnail-cut diamond (lacking its original setting) that he bought from Cronan last year. Rocking gently on Zucker’s desktop, it shoots off chartreuse lights.