ABSTRACT
Vacuum metal deposition (VMD) is an extremely sensitive technique for the development of latent €ngermarks on nonporous and semiporous surfaces. VMD is generally recognized as being more sensitive than cyanoacrylate fuming, which is the most common routine development technique for nonporous surfaces [1-3]. The increased sensitivity achieved with VMD is particularly evident in instances where marks are old, have been exposed to adverse environmental conditions, or are present on otherwise dif€cult surfaces [4,5]. A further advantage of VMD is that, with normal development, the substrate is covered with a layer of metallic zinc that can assist in overcoming background interference such as heavy printing or multicolored patterns. VMD is generally not considered a routine method for €ngermark development due to the expense of the equipment (Figure 10.1), the time required for application of the technique, and the need for experienced operators to obtain optimum results.
