Soap mummy and grave wax

 Archaeology 2011 01 04 Soapman-Zoom

Above is a "soap mummy" from the collection of Smithsonian Museum of Natural History. This person lived in Philadelphia during the 18th century. After he was buried, water leaked into his casket and converted his body fat to soap, specifically adipocere, known to the trade as "grave wax." Soapman: The Mummy Made of Soap (Discovery, thanks Bob Pescovitz!)