LONDON — It was among the first questions asked after news of the engagement hit the press: What does Kate Middleton’s engagement ring look like?
That evening at St. James’s Palace, the world finally got a glimpse of a ring that looked familiar: The 18-carat oval sapphire surrounded by diamonds was the one worn by Princess Diana.
"I just hope I look after it," Middleton said on Tuesday.
Diana chose the ring from several shown to her in 1981 for her engagement to Prince Charles. But her choice at the time didn’t come without a scandal.
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Scoffers — including some in the royal family — said that the future princess had chosen a ring that anyone could buy, instead of having one custom-made. At the time, it cost $60,000.
But Princess Di had an eye for style even then, and that “commoner's sapphire” has borne her name ever since. She wore it even after her divorce from Prince Charles.
Video: The story of Princess Di’s sapphire ring (on this page) After Diana’s death, the ring reportedly came into Prince Harry’s possession, while William inherited a Cartier watch. Harry apparently then decided that the ring should be on the finger of the future queen of England and gave it to William to give to his fiancee.
"Obviously, she's not going to be around to share in any of the fun and excitement of it all, so this is my way of keeping her sort of close to it all," William said of his late mother in a joint interview with Middleton on Tuesday.
Before leaving on the trip to Kenya during which he proposed to Kate, William took the ring from a royal safe in what Britain’s Daily Mail newspaper described as a “cloak-and-dagger” operation.
William carried the ring around with him in his “rucksack” for three weeks in Africa before he finally popped the question.
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During Kate and William’s interview on British TV a few hours after news of their engagement was announced, the dazzling sapphire was set off nicely by the navy silk jersey dress Kate wore with simple black pumps. The dress was by London-based fashion label Issa, Middleton’s favorite designer.
“I’m very happy that she has chosen to wear Issa today,” Daniella Helayel, an Issa designer and friend of Middleton’s, told People magazine Tuesday. The choice fueled speculation that Middleton may wear Issa on her wedding day.
Minutes after the ring was unveiled, jewelry stores around the world started getting calls.
“I called my wife and said, ‘Honey, I’m not coming home tonight!’ ” said Michael Arnstein, the CEO of New York’s Natural Sapphire Co. “We’re in a frenzy. This is changing our business overnight.”
The company took calls from Britain, Canada, the United States and elsewhere requesting replicas of the ring.
“It’s the biggest news for our company since Princess Diana received her sapphire,” said Arnstein, adding that after Diana’s engagement to Charles, the same ring also was responsible for a surge in business.
“Now, it’s turned into a legacy,” he said.
He planned to work into the night, asking his employees to stay as long as possible. Accounting for international time differences, more calls from Asia were likely to follow.
Most customers couldn’t afford an exact copy of the royal ring: The sapphire alone is worth about $300,000 retail, and the whole ring about a half-million dollars, Arnstein estimated. Using high-tech, 3-D computer software and modeling machines, he’s producing replicas costing mostly $1,000 to $2,500 using 1- or 2-carat certified sapphires surrounded by tiny diamonds also set in 18-karat white gold.
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“They’re just as beautiful," said Arnstein, who’s so immersed in the specialty gems that he even stocks his company bathrooms with bottles of the Elizabeth Taylor-tagged perfume Diamonds & Sapphires.
He also sells sapphires to other jewelers — including a 69-carat one the size of a quail’s egg that’s worth more than $1 million.
Sapphires are rarer than diamonds but less expensive because demand for them is lower. They’re especially beloved in Britain and its former colonies, including Sri Lanka, which Arnstein plans to visit soon to buy more of the sapphires mined there — expecting an uptick in demand through the holidays.
The Associated Press contributed to this article.