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Click here to view the Henry Classification System.

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1 Click here to view the Henry Classification System

2 Loops- depends on which hand it is found on makes it either: RadialUlnar Radial loops start on the thumb-side of the finger, the side closer to the radius bone Ulnar loops start on the pinky-side of the finger, the side closer to the ulna, the lower arm bone. wikipedia.org

3 Arches Plain Arches Tented Arches If you compare the two images, plain arch and tented arch, you can see that while the plain arch tends to flow rather easily through the pattern with no significant changes, the tented arch does make a significant change and does not have the same "easy" flow that the plain arch does. The technical definition is that a tented arch has a "significant upthrust" where a plain arch does not. http://www.policensw.com/info/fingerprints/finger07.html

4 Whorls Between 25 and 35 per cent of the patterns encountered consist of whorls. In a whorl, some of the ridges make a turn through at least one circuit. Any fingerprint pattern which contains 2 or more delta's will be a whorl pattern. In the scheme of classification you can make the assumption that if a pattern contains no delta's then it is an arch, if it contains one (and only one) delta it will be a loop and if it contains 2 or more it will always be a whorl. If a pattern does contain more than 2 delta's it will always be an accidental whorl. PLAIN CENTRAL POCKET DOUBLE LOOP ACCIDENTAL

5 Minutiae

6 Collection with Powders Dusting Powders Magnetic Powders Powders may be applied with a fingerprint brush, a brush with extremely fine fibers designed to hold powder, and deposit it gently on the fingerprint to be revealed, without rubbing away the often delicate residue of the fingerprint itself. They may also be applied by blowing the powder across the fingerprint, or by pouring the powder onto the print, and then blowing away the excess. Magnetic powders are also used, where a fine magnetic powder is held by a magnetic applicator, which may then be gently moved across the fingerprint. As no bristles touch the surface, this often damages the print less than other methods of developing the print. Fingerprint powders have various formulations, and the appropriate powder must be used on the appropriate surface. For example, dark coloured powders will show up a fingerprint far better on a light surface. wikipedia.org

7 Cyanoacrylate (Superglue)Fuming Cyanoacrylate fuming is a widely used forensic tool for the development of latent fingerprints, however the mechanistic details of the reaction between the fingerprint residue and the cyanoacrylate vapor are not well understood. Here the polymerization of ethyl- cyanoacrylate vapor by sodium lactate or alanine solutions, two of the major components in fingerprint residue, has been examined by monitoring the time dependence of the mass uptake and resultant polymer molecular weight characteristics. This data provides insight into the molecular level actions in the efficient development of latent fingerprints by superglue fuming. The results show that the carboxylate moiety is the primary initiator of the polymerization process and that a basic environment inhibits chain termination while an acidic environment promotes it. The results also indicate that water cannot be the primary initiator in this forensic technique. http://www3.interscience.wiley.com/journal/118519289/abstract?CRETRY=1&SRETRY=0http://www3.interscience.wiley.com/journal/118519289/abstract?CRETRY=1&SRETRY=0 ` To See a Video, Click Here

8 Iodine Fuming The iodine fuming technique has historically been recognized as one of the earliest techniques available to the investigator for developing latent prints. Prior to the introduction of chemical methods, such as ninhydrin, iodine fuming was a preferred and recommended method to be used on paper products. Iodine fumes are sensitive to different latent residues than other methods. It is possible that latent prints that would have been developed by iodine fumes will not be developed by other means, whose application will then destroy the residue needed for iodine development. When the nature of surface is questionable as to a particular technique, or sequence of techniques, iodine fuming should definitely be considered. That was the case some years involving a piece of surgical tape. To read more, click here To read more, click here

9 Ninhydrin Spray Ninhydrin, an amino acid reagent, may be applied to porous surfaces in a variety of solutions to develop latent finger and palm prints. The choice of application depends on the surface being processed, the expertise of the examiner, and the equipment and supplies available. …Choosing the correct formula and method in any given situation will maximize the chances of success while minimizing the hazards, both to the examiner and the evidence. http://www.geocities.com/cfpdlab/ninhydri.htm


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