Numerous methods of staining are used to develop or enhance blood-contaminated latent prints. These methods depend on staining the protein components of blood to form a more visible impression, commonly a dark blue or black. Among these methods are Amido Black, LeucoCrystal Violet, Coomassie Blue, and Acid Fuchsin. Amido Black has also been used to develop and enhance footwear and tire track impressions. Acid Yellow 7 stain is one of the newer and more effective fluorescent stains used to enhance bloody footwear and fingerprint impressions on non-porous surfaces. Staining reveals a yellowish-colored print which fluoresces under blue-green light (400-490 nm). When lifted with a white gelatin lifter, the impression will often reveal enhanced fluorescence. Available as ready-to-use premixed liquid stains and destains.