Prints left on guns and bomb casings tend to be patterns left by human sweat and, as such, are not easy to reveal using established techniques that employ powders and other chemicals.
Instead, Professor [Neil] McMurray measures the tiny electrochemical reactions that result when fingers touch metal.
A device called a Scanning Kelvin Probe is used to measure the tiny changes in electrical potential caused by these reactions.
The technology can be used to find fingerprints on objects like bullets and shrapnel. Wild.
The article also has information on how the chemical signature of fingerprints can be affected by things like a person’s age and whether he uses drugs.
