Tool mark determination in cartilage of stabbing victim

Striations produced on rib cartilages by a knife were conclusively matched with the individual characteristics of the cutting edge of the knife. This was accomplished using Dip-Pak (cellulose acetate butyrate), Coe-Flex (polysulfide dental impression), and comparison microscopy. An absolute identification was made in which all significant striae matched the individual characteristics of the blade's cutting edge.