Materials and their properties - (CCEA)Using material to fight crime

Collecting fingerprint evidence

Fingerprint evidence can be collected using powders:

• on a white surface use carbon black powder;
• on a black surface use aluminium powder.

The powder is dusted on and then any excess powder brushed off.

A piece of cello tape is then used to transfer the print onto card or a glass slide for further analysis.

Visualising fingerprint evidence

Fingerprints can also be visualised using alternative light sources, such as UV light or chemical developers, such as iodine fumes.

A photograph or scan of the fingerprint can then be compared to a database of fingerprints to identify an individual.