Palm Prints and Print Processing Quiz 5 Flashcards
Palm Characteristics
3 Regions.
3 major creases (top, middle, left).
Left hand: Waterfall left.
Right hand: Waterfall right,
Palm Regions
Thenar (thumb).
Hypothenar (pinky).
Interdigital (fingers).
Interdigital Region
Wavy flow: ridges flow down, over, up, and out.
Tri-radii.
Tri-Radii
Convergence of ridges.
Ridges flow in, away, and up.
Looks like a delta.
Found primarily in the interdigital region, but also sometimes in the hypothanar region.
Hypothenar
“Writer’s palm”.
Down and out formations: ridges flow down and out from the interdigital to hypothenar.
Edge creases: more defined and different directionality than thenar edge creases.
Fingers: General
Ridge flow of fingers is inner to outer.
1 crease between 1st and 2nd joint.
2 creases everywhere else.
Fingers: First Joint
First joint always has a pattern.
If no observed pattern, it is not the first joint.
Fingers: Third Joint
Down and out ridge flow on index and pinky.
Wavy ridge flow middle and ring.
Has hash marks and flexion creases.
Fingers: Second Joint
Second joint ridges in a linear fashion.
Follow flow of arrows.
Skin Conditions
Displasya.
Psoriasis.
No ridges.
Displasya
Refers to an abnormality in the mutation of cells within a tissue.
Latent
Hidden. Refers to any print that must be enhanced chemically or physically to be made visible.
Leaving a Latent Print
Simply sweat exuded from the body.
Friction ridge skin does not exude oil. If present, it is picked up from another area of the body.
Basic Types of Print Processing.
Physical.
Chemical.
Types of Physical Processing
Powdering.
Mikrosil/Accutrans/Forensic Sil.
Types of Chemical Processing
Cyanoacrylate Fuming (Super-glue). Ninhydrin. RAM. Rhodamine. Ardrox.
Powdering
Application of finely ground colored powder.
Always on a non-porous surface.
Makes latent prints visible.
Powdering: How it Works
Powder clings to moisture, oil, or other residues left behind when friction ridges touch an object.
Characteristics of Powder
Passable through 200-mesh screen.
Possesses adhesive qualities.
Free-flowing and non-clumping.
Not caustic, toxic, or carcinogenic.
Powdering: Surfaces
Best used on smooth, non-porous surfaces.
Glass.
Metal.
Finished Wood.
Plastics.
Not suitable on wet, rough, or tacky surfaces.
Powdering: Considerations
Always consider effects of powdering on forensic exams.
Before using powder, conduct careful visual examination of each item.
Powdering: Order
Powder applied after super-glue process.
Once an item has been powdered, no further latent print examinations can be performed.
Powdering: Colors
White.
Gray/Silver.
Black.
Magnetic.