Basic Shapes/Patterns of Fingerprints & Collecting/Lifting Fingerprints

Collecting/Lifting Fingerprints:

There are multiple ways to collect prints but we discussed two different kinds in class. The first kind was using white powder on darks surfaces and the second was collecting prints on glass surfaces. For the first one, we laid down fingerprints on a black tabletop. Then we experimented with different techniques for making the print visible with the powder. Finally we then took tape, applied it to the print, and then placed it on a black piece of construction paper, which made the print visible. For the second method, first we got into groups of four. Then we placed a print on a glass jar. After that, we applied black powder to the surface, trying to make the print visible. Finally we placed tap on the now visible print and then placed it on a white piece of paper, to make it visible. We repeated this experiment three times so that we have three sets of prints.

Basic Shapes/Patterns of Fingerprints:

Three major classifications of the patterns and shapes of fingerprints:

Arches:

• The ridges go across the finger but do not make backward turns
• There are two types of arches: Plain arch, tented arch
• Plain arch
• The ridges go directly across the finger with no backward turns.





Plain Arch

• Tented arch
• Similar to Plain arch only they contain a “delta”.



Tented Arch

Loops:

• Loops contain one delta, and on one side of that delta the ridges curve and go backwards.
• Loops are determined by which direction they face: Ulnar, Radial
• Ulnar loops
• Loops that flow toward the little finger





Ulnar Loop

• Radial loops
• Loops that flow toward the thumb

Radial Loop

Whorls:

• Whorls contain two or more deltas and have some ridges that go in a circle at least one time
• There are four different types: Plain whorl, central pocket whorl, double-loop whorl, and accidental whorl
• Plain whorl
• Whorl that contains two deltas and has two or more ridges that flow in a circle





Plain Whorl

• Central pocket whorl
• Whorl that contains two deltas and has two or more ridges that flow in a circle. They also have an obstruction at right angle o the flow.





Central Pocket Whorl

• Double-loop whorl
• Whorl that contains two separate loops, two deltas, and one or more ridges that flow in a circle.



Double Loop Whorl

• Accidental whorl
• Contains two different patterns(other than plain whorl) with two deltas or a pattern that contains one, or doesn’t fit the descriptions of the other types.

Accidental Whorl