Basic ink types that have been in use over the past centuries include those based on carbon black pigments, iron gall inks, and bister. The latter two turn brown with age and are difficult to distinguish. Chemical or spot testing on pen and ink drawings may destroy either ink or support. Ultraviolet (UV) and infrared (IR) illuminations have been found to be useful in such identification procedures; the findings were corroborated by artificial aging tests using an environmental chamber and a fluorescent light bank. The materials, equipment, and procedure are described. Iron gall detected by fluorescing halo can indicate potential damage to the paper before deterioration itself becomes visible.