Pattern Finder Reference
Pattern Finder
Forensic Identification Guide
REF: ID-FINGER-001
65%
Loop Patterns
30%
Whorl Patterns
5%
Arch Patterns
The Loop Family Most Common
Delta
Ulnar Loop
Ridges flow in from and out toward the little finger side.
Delta
Radial Loop
Ridges flow in from and out toward the thumb side.
The Whorl Family
Plain Whorl
At least one ridge makes a complete circle. Contains two deltas.
Double Loop
Made of two separate loop formations. Often called an "S" pattern.
The Arch Family Rarest Type
Plain Arch
Ridges enter one side, rise slightly in the center, and exit the other side.
Tented Arch
Similar to the plain arch, but has a sharp upthrust or spike in the center.
Feature: Core
The approximate center of the fingerprint pattern, usually found in loops and whorls.
Feature: Delta
A triangular area where ridges radiate in three directions. Loops have one; Whorls have two.
Ridge Count
The number of ridges intervening between the delta and the core of a loop pattern.
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