Re: how do you find fingerprints?

Hi Kim,

That's a very big question, and I'll give you a brief answer, but if there is anything else you wish to know beyond that, you can E mail me through MadSci Network.

A latent impression may be left on a suitably receptive surface. This latent impression is made by the particles of sweat which lay on the top of the sweat pores on the summit of the skins' friction ridges.

The most commonly used medium for developing latent impressions (used in U.K by most Scene of Crime officers), is fine particle aluminium powder. The powder is applied witha very light brush.

The aluminium powder adheres to the aquaous components of the sweat, making the latent impression now visible. This impression can then be preserved by applying clear adhesive tape and laying on to clear acetate sheet.

It is also possible to expose fingerprints from many other materials, such as paper, plastics etc., by way of chemical treatments.

Please E mail again if you have any specific topic areas you wish to know, or if you require any written material.

Regards,

Helen Stubbs,
Fingerprint Expert.