Among her many legacies,XDY Exchange one of Princess Diana's most popular is her iconic sense of style.

Not only did she immortalize the biker short and crewneck look, her looks also often made subtle commentary on the royal family and her place within Buckingham Palace (case in point, her off-the shoulder black, revenge dress). Another such item of clothing? Her "One Black Sheep" sweater. From a small brand called Warm and Wonderful and worn to a polo match in 1981, the red, wool sweater was patterned with white sheep save for one black sheep on the front. 

Now over forty years later, the sweater—which was interpreted at the time as signifying Diana's feelings as an outsider among the royal family—was put up for auction and subsequently earned the highest price paid for a piece of clothing worn by the late royal. 

So, just how much did the knit garment earn?

At Sotheby's recent Fashion Icons auction in New York, the sweater fetched a total of $1,143,000. A sale that jumped from $115,000 to the $1.1 million total within the last fifteen minutes, per CNN. 

Princess Diana's fashion choices also made headlines recently when her images of her spare wedding dress were revealed for the very first time. 

Created as a back-up in case the original gown designed by David and Elizabeth Emanuel was leaked, this second gown bore many similarities to the actual dress Diana wore in her 1981 wedding to the now-King Charles III at St Paul's Cathedral in London.

"The dress was made in pale ivory silk taffeta with embroidered scalloped details on the hem and sleeves," Elizabeth told Hello! of the second gown in an interview published Aug. 5. "Tiny pearls were sewn on the bodice."

But the gown was always meant to be a back-up, and Elizabeth, David and their team Brook St, Mayfair took every precaution to ensure the main dress remained a secret. 

"We had the dress stored every night in a metal cabinet guarded by two guards, Jim and Bert," the British fashion designer added. "So there was somebody there 24 hours a day and we put shutters on all our windows, and we put false color threads in the rubbish bins because people were going through our bins."

Over the years, countless women have emulated the late Princess' style, including Kate Middleton herself. 

Of why Diana's style has been so enduring, Eleri Lynn, the exhibit creator for Diana: Her Fashion Story, told Vanity Fair in 2017, "She had really sort of transcended fashion and achieved an incredible chic and elegance. All you saw was her, and the clothes became secondary to her own presence and her work."

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