Fingerprint Ridge Characteristics (minutiae)
According to criminal investigators, the use of fingerprints follows 3 fundamental principles:
A. A fingerprint is an individual characteristic because no two fingers have yet been found to possess
identical ridge characteristics.
B. A fingerprint remains unchanged during an individual’s lifetime.
C. Fingerprints have general ridge patterns that permit them to be systematically classified.
In order to conclusively match individual fingerprints, fingerprint examiners use ridge characteristics,
also known as minutiae. The most common types of ridge characteristics are bifurcations, ridge endings,
and islands, though there are several different categories and subcategories for each of these.
A single rolled fingerprint may have more than 100 different ridge characteristics.
In the United States there in no minimum number of ridge characteristics that must be used to match up
two fingerprints (though eight or more is considered “standard” and twelve is “sufficient”). However, the
match must be made by one verified fingerprint examiner (usually trained by the International
Association for Identification (IAI)) and verified by second verified examiner.
Table 1: Fingerprint ridge characteristics (minutiae)
Fork
Double Fork
Triple Fork
Delta
Dot
Bridge
Hook
Eye
Short Ridge
Ending Ridge
NAME:____________________________
Figure 1: Practice the identification skills
1.
2.
3.
Examine the fingerprint in Figure 1
To which class does the fingerprint pattern belong? _________________
Use Table 1 to help identify fingerprint ridgeline details (minutiae). Locate and label at least 8
positions of ridgeline details in Figure 1.
e.g. fork