(CNN) -- Supermodel Naomi Campbell took the stand Thursday in the trial of former Liberian President Charles Taylor and said she received a gift of "dirty-looking stones" that she assumed was from him. Campbell was handed the stones following a dinner hosted by Nelson Mandela in 1997. "When I was sleeping I had a knock on my door. I opened the door and two men were there. They gave me a pouch and said, "A gift for you.'" The men didn't introduce themselves nor say anything else, Campbell said. The next morning, she opened the pouch and saw a few "very small, dirty-looking stones."
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Naomi Campbell tells trial she received small pouch of "dirty-looking" stones 13 years ago
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Tells trial that two men knocked on her door in the middle of the night
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Says she assumed they were from Charles Taylor after it was suggested he may have been behind the gift
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Taylor faces war crimes charges over a conflict in Sierra Leone
Prosecutors say @placeholder gave Campbell a diamond during the war in Sierra Leone, contradicting Taylor's testimony that he never handled the precious stones that fueled the conflict.