French Blue

gem

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June 26, 2026

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The French Blue was a large, sapphire-blue gemstone from India, believed to be cut from a 112-carat stone. It was acquired by King Louis XIV of France in 1668 and became part of the French crown jewels. This stone was later recut into a 67-carat heart shape and disappeared during a robbery in 1792. The renowned 45.5-carat Hope diamond, currently displayed at the Smithsonian Institution, is thought to have originated from the French Blue. The Regent diamond, another significant French crown jewel, is a brilliant-cut stone with a blue tinge, discovered in India in 1701 and weighing 410 carats in its rough form.12

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Hope diamond
This stone, later called the French Blue, was recut into a 67-carat heart in 1673 and disappeared after the crown-jewel robbery of 1792. The 45.5-carat Hope diamond, named for the London banker Thomas Hope, who purchased it in 1830, was apparently formed from it. The Hope diamond is on display…
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This stone, later called the French Blue, was recut into a 67-carat heart in 1673 and disappeared after the crown-jewel robbery of 1792. The 45.5-carat Hope diamond, named for the London banker Thomas Hope, who purchased it in 1830, was apparently formed from it. The Hope diamond is on display…
Read More