In 1877, a dazzling 287-carat yellow diamond was unearthed in South Africa’s Kimberley mine. The next year, Charles Lewis Tiffany bought it for $18,000—and turned it into a legend.

Tiffany sent the rough stone to Paris, where it was cut into a brilliant 128.54-carat cushion with 82 facets—far more than usual—to enhance its glow. It became the ultimate symbol of Tiffany & Co.'s elegance and ambition.

Despite its fame, the Tiffany Diamond has never been for sale. It’s only been worn publicly four times—by Audrey Hepburn, Lady Gaga, Beyoncé, and a New York socialite at a 1957 ball. Today, it resides at Tiffany’s flagship store in New York, still off-limits to buyers but open to awe.