The Sirchie Amido Black Dye (25g) is useful for enhancing latent prints contaminated with blood, but it will not successfully develop a normal perspiration-based print. Although it will not detect the typical chemical components of latent prints, Amido Black is very sensitive to the proteins found in blood and some other body fluids. It leaves a blue-black stain and is usable on both porous and nonporous surfaces. It should be used only after all other physiological samples have been gathered and all other fingerprint development methods have been attempted. Instructions and formulations are included.