JAMES KING-HOLMES / SCIENCE PHOTO LIBRARY JAMES KING-HOLMES / SCIENCE PHOTO LIBRARY
Fingerprints on banana. Close-up of fingerprints revealed on a banana by magnetic fingerprint powder - a new invention used to detect prints on surfaces impossible to check by conventional means. The powder consists of tiny iron flakes with an organic coating that makes them stick to the greasy residue in a fingerprint. Excess powder is removed by a magnet, removing the need for brushing and hence leaving intact the delicate ridge lines that make each print unique. The technique gives sharper results and works on difficult surfaces like plastic bags, magazine covers, wallpaper and wood.
Model release not required. Property release not required.