§Ninhydrin—reacts with amino acids to produce a purple color.
§Silver nitrate—reacts with chloride to form silver chloride, a material which turns gray when exposed to light.
§Cyanoacrylate—“super glue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit.
• In
modern labs and criminal investigations, lasers and alternative light sources are used to view latent
fingerprints. These were first used by the FBI in 1978. Since lasers can damage the retina of the eye, special precautions must
be taken.