Princess Diana's iconic black sheep sweater sold at auction for a whopping...

A red sweater worn by Princess Diana soon after her engagement to then Prince Charles has been sold for $1.1 million at an auction, Sotheby's announed on Thursday. The iconic sweater had several white sheep on it and one black sheep.

Princess Diana wore the sweater to a polo match in 1981 during her royal in-the-making days,

Called the "Black Sheep" sweater, it became quite popular and is now a symbol of Diana's difficult time as a royal. It was sold for a whopping amount of $1.1 million which was much more than what the experts expected. Sotheby's earlier expectation was that it would sell between the price range of $50,000 to $80,000.

This black sheep sweater was designed by Sally Muir and Joanna Osborne and their knitting company Warm and Wonderful, which was not popular at that time. However, the designers garnered fame after Diana sported their sweater.

Because of the high demand for this sweater, the auction lasted longer than expected. The price went up from $190,000 to $1.1 million in just 15 minutes at the end.

Sotheby's in a statement said that this is the highest price ever paid at auction for a garment that belonged to Princess Diana. The sweater sold at an even higher price than her fancy ball gown which was sold for $604,000 in January. Moreover, it's the most expensive sweater ever sold at an auction.

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