Page 15 - Read The Found Prints Fingerprint Analysys
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Development of latent prints can be achieved (silver nitrate-based reagent). Iodine fuming is
through chemical, powder, lighting, and the oldest method used for visualizing latent
photographic methods. The method of treatment prints. Iodine crystals are heated in a chamber
depends on the surface where the print is located. with the latent print and the iodine fumes that
Prints on non-absorbent surfaces (e.g. mirror, form combine with the oils in the latent print to
tile, and painted wood) can be developed by make it visible. Iodine prints, however, are not
treatment with powders or cyanoacrylate (Super permanent and are, thus, quickly documented
Glue). The powder type used varies based upon and photographed. Many new chemical treatment
the background of the print. Some examples processes are now available. Latent prints may
are black powder, magnetic-sensitive powder, also be developed through fluorescent techniques.
and fluorescent powder. Super Glue fuming has Some of the techniques include the use of an argon
become a popular test for non-absorbent surfaces. ion laser (natural fluorescence by components
In this test the cyanoacrylate ester in the super of perspiration and blood), alternate light source,
glue interacts with a latent print to give it a white Reflected Ultraviolet Imaging System, and dyes
appearance. and powders as discussed above. The most widely
used fluorescence technique in labs and crime
For porous surfaces (e.g. cloth, paper, and scenes is the alternate light source. An alternate
cardboard) chemical treatments are utilized, such light source is any high intensity light source, other
as iodine fuming, ninhydrin, or physical developer than a laser, that filters the origin light and induces
THE MYSTERY OF LYLE AND LOUISE 15
