Princess Diana's friend is auctioning off a unique diamond-encrusted bag in her honor

Even 20 years after her death, Princess Diana is still giving to causes - most recently she will be giving to the American Red Cross thanks to an auction of one of her handbags. A diamond-encrusted purse designed exclusively for the British royal by her best friend is to sell at charity auction for close to $40,000.

Diana personally asked Lana Marks to create a 'one off' handbag for her in 1995. Lana came up with a dazzling top-handle tote which Diana described as "the most beautiful handbag imaginable."

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The green bag inspired by Princess Diana will go up for auction on September 26 in Beverly Hills Photo: SWNS

The Princess sent Lana a handwritten thank you note and was so impressed she ended up buying 15 of the bags. Now, to mark the anniversary of her passing, the bag designer has created a one-of-a-kind edition of the luxury bag. The jewel-encrusted handbag, which is part of Lana Marks' signature range, is rich emerald green and made from crocodile skin. It features a soft heart clasp encrusted with 225 3.22 carat white diamonds set by hand on 18k yellow gold.

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Lana said she designed the latest Princess Diana bag because she wanted to do "something special" for her late friend. "She would love the bag and it reminds me of her. The heart is particularly soft and rounded. It may appear very simple but it is not," the South African designer noted. "She was the princess of hearts. I want people to remember this beautiful person. She was somebody who inspired."

The British royal loved carrying Lana Marks bags, seen here in April 1997 Photo: Getty Images

Experts estimate the unique lot will fetch around $19,000 to $38,000 for the American Red Cross when it goes under the hammer next month. Diane D'Amato, Director of Luxury Accessories at Heritage Auctions, said: "When Lana Marks and Princess Diana met they became friends instantly. They had a very special relationship. They would call and speak to each other. It was much more than just a business relationship."

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The auctioneer continued: "Now that it is 20 years ago that Princess Diana passed, she had an idea to create a one-of-a-kind bag to sell, with all the proceeds going to the American Red Cross. She wanted to pick a charity that was near and dear to Princess Diana's heart. We have never done this before and Lana Marks has never created a bag like this before. This is honouring Diana's memory and we are expecting a lot of interest."

Diana sent Lana a handwritten thank you note after she received one of her purses Photo: SWNS

Lana has designed luxury handbags for the likes of Kate Winslet, Drew Barrymore, Angelina Jolie, Helen Mirren, Charlize Theron, Chloe Sevigny, Lucy Liu and Jennifer Aniston. She is also the purveyor of handbags to the most prominent royal families in the world. The Diana bag will be up for auction at Heritage Auctions in Beverly Hills on September 26, with bidding kicking off on September 5.

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