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Experiment 7 Cyanoacrylate “Super Glue” Fuming Technique to Develop Latent Fingerprints

Chemical fuming has a long history of use in latent fingerprint development. For nearly a century, forensic investigators have been using the fumes coming off warmed crystals of iodine to develop latent fingerprints on paper. Normally the procedure involves hanging the paper in a closed fuming chamber containing a small tray of iodine crystals. The chamber is closed and the iodine crystals are gently heated using a hot plate. Upon warming, the solid crystals of iodine sublime, or go directly into the vapor phase, and saturate the environment in the small chamber. The iodine fumes then interact with the invisible or latent fingerprint residues present on the paper and form brownish-colored visible prints.