Observing and Taking Fingerprints
Although fingerprints can be left casually on anything you touch, there are a number of steps involved in
taking clear fingerprints that can be classified and used for identification.
Materials:
- magnifying glass
- fingerprint ink or ink pad
- 10-print identification paper
Procedure:
1. Observation: Examine the surface of your fingers (where your print can be found).
a. On a separate sheet of paper, describe what you see.
b. Make a sketch of what you see.
2. Ink and transfer procedure: The purpose is to obtain as wide and clear a print as possible – not too
light, not too dark. This takes practice. The idea is to roll the finger across the ink pad, then roll it across
the paper of the fingernail to the other. Do this roll just ONCE – NOT back and forth because it will
smudge the print. Rolling the finger should make a large, square print showing lots of detail. Practice
on a piece of scrap paper BEFORE using your 10-print ID paper.
3. Ink and transfer: Complete your 10-print ID as listed on your paper.
4. Further Observations: Examine your 10-print card using a magnifying glass. On a separate sheet of
paper (same piece used for step 1):
a. Note basic similarities and differences in the patterns. What are they?
b. Note cracks, scars, and other unique features.
c. Calculate your primary classification number.
Loop
Arches
Whorls
Minutiae
What is your primary classification number?
Each finger is given a point value. Assign the number of points (assigned in the image below) for
each finger that has a WHORL and substitute into the equation. If there is no whorl, you put a 0.
Right index
+
right ring
+
left thumb
+
left middle
+
left pinky
+
1
=
Right thumb + right middle + right pinky
right
+
left index
+
left ring
left
+
1