The Cut-Off Finger
A woman is shopping at a mall while her boyfriend or husband is waiting outside. Near closing time, the woman cannot be found. The boyfriend/husband asks security to help him find her. They find her in the fitting room having fainted. The reason is because someone, known to be a black assailant, cut off one of her fingers to obtain her diamond ring. She lost blood and had to be rushed to the emergency room for treatment. The man who did this was never caught.
A separate legend states that the thief had been caught, on the bus or subway, with the severed appendage in his pocket dripping blood with the diamond ring as well. This legend is known in the United States but is more popular in Spain, Sweden, and Columbia.
(Source: Brunvand, Jan. Encyclopedia of Urban Legends. 2001.)