An experimental butchery of a goat was performed at the site of Olorgesailie, Kenya, utilizing tools made from local source rock. The prescence of blood on the experimental tools was tested with a series of commercially available polyclonal antisera. Blood could be identified immunologically on the experimental tools, and laboratory exposure to UV irradiation effectively all immunoreactivity of the blood on the lithics. Verification of the source of the blood as goat was oobserved in the relative reactivity of these antosera through a small range of dilution of the rock extract. Albumin was identified as part of the protein fraction remaining on the tools; IgG was not preserved at nanogram levels of detection. These experiments illustrate the importance of (1) antiserum concentration, (2) antigen (tool extract) concentration and (3) environmental impacts such as sunlight in the interpretations of residues extracted from stone tools.