Lifting Prints

When a fingerprint is found, certain procedures and precautions are taken in order to make sure it is lifted safely and undamaged.

LIFTING FROM A DARK, SOLID SURFACE (such as a lab table)

1. When a fingerprint is suspected to be in an area, lightly dust the spot with white talc powder, then blow on it softly in order to remove excess powder. This action should also reveal where powder is stuck in the ridges of a fingerprint.
2. With a soft brush, brush around the fingerprint until it is relativly isolated from other powdered sections and easily visible.
3. Take clear tape and carefully place it onto the revealed print. When you pull the tape back, talc powder should outline the fingerprint on the tape.
4. Press tape gently onto a black card. Now the fingerprint has been successfully lifted.
   

LIFTING FROM A LIGHT, SOLID SURFACE (such as glass)

1. When a fingerprint is suspected to be in an area, lightly dust the spot with black carbon powder, then blow on it softly in order to remove excess powder. This action should also reveal where powder is stuck in the ridges of a fingerprint.
2. With a soft brush, brush around the fingerprint until it is relativly isolated from other powdered sections and easily visible.
3. Take clear tape and carefully place it onto the revealed print. When you pull the tape back, carbon powder should outline the fingerprint on the tape.
4. Press tape gently onto a white card. Now the fingerprint has been successfully lifted.

Certain chemicals are used to develop prints on other surfaces.

Iodine: Fuming a fingerfrint with iodine vapor will cause a reaction in which the gas is absorbed by the oils of the fingerprint, turning it dark brown or black. Often used on paper.

Cyanoacrylate: Cyanoacrylate is a chemical that makes up about 98% of super glue. When mixed with sodium hydroxide, it will create fumes that react with amino acids in a fingerprint, creating a visible white print.

Silver Nitrate: Silver nitrate reacts with chloride in fingerprints to form silver chloride, which shows up in a reddish-brown hue under ultraviolet light.