VMD processing is well known for developing latent prints on polythene and non-porous items with the use of Gold and Zinc.

Metal + Substrate Guide

VMD will develop latent prints on almost any substrate and it is important to understand that the use of other metal processing will increase the chances of latent print recovery.

Processing Order of Metals

Gold and Zinc can always be used first in the processing order.  If no prints are developed, be sure to process the item with a single stage metal.  At GoEvidence Forensic Laboratories we use the Silver on a regular basis, followed by Zinc.

Until a VMD user is familiar with the proper metals to use on a substrate, it is helpful to keep a substrate and consumable log to validate what metal development gives you the best results. Until you have the knowledge of what metals work best, the first and safest step is to process with Gold and Zinc, examine and photograph . The second step can be a single stage metal (Silver, Sterling Silver, Aluminum, Copper, Tin, etc.). Process, examine and photograph.   Zinc will be the final metal process if desired.

There are latent prints that do not develop with the gold and zinc. Therefore, it is essential to process the item with a single stage metal (e.g. silver, sterling silver, aluminum, copper, tin, etc.). You can get a silver/chrome contrast on dark substrates by using zinc for the final metal process.

      Developing latent prints

      Using VMD, we have developed hand marks and latent print ridge detail on all of the substrates listed below

      Items with an asterisk (*) may only develop with a single stage metal. Should be processed with a single stage metal to increase latent print recovery. For a chrome/silver contrast, use zinc for the final metal process.

      Porous Surfaces

      • Paper  
      • Cardboard
      • Photo Paper
      • Thermal Paper
      • Carbon Paper

      Fabric + Currency*

      • US Currency (dollar bills)
      • Silk, Satin, Nylon & Polyester have a high thread count and level 2 ridge detail can be developed.
      • Cotton, Suede, Denim & Corduroy will show finger and palm marks.   

      Untreated Wood / Wetted Paper*

      • Wetted paper and untreated wood 

      Paper with Plastic*

      • Paper Envelope with Plastic Window
      • Paper with Transparent Tape

      Adhesive + Non-Adhesive Sides of Tape*

      • Transparent Tape
      • Duct Tape
      • Electrical Tape
      • Masking Tape

      Semi-Porous Surfaces

      Waxed Paper + Cardboard*

      • Polymer Banknotes
      • Photo Paper
      • Paper Magazines
      • Advertising Brochures
      • Cardboard Boxes
      • Milk Cartons
      • Cups & Plates

      Soft Vinyl, Leather, & Rubber*

      • Vinyl
      • Leather
      • Rubber Gloves  
      • Latex Gloves

      Plastic with Paper*

      • Prescription Medicine Bottles - the use of sliver or sterling silver will develop the paper and the plastic with a single run in the chamber. Gold and zinc may only develop the paper.

      Non-Porous Surfaces

      Packaging Material*

      • Polyethylene Plastics
      • Styrofoam

      Recycled Plastics*

      • Polyethylene
      • Plastic Tarps
      • Household Electrical Face Plates & Outlets
      • Hardware Parts & Tools
      • Automobile Plastics
      • Electronic Devices
      • Medicine Bottles
      • PVC Conduit

      Textured Plastics & Coated Metals*

      • Teflon
      • Powder Coated Metals
      • Tools & Firearm Coatings
      • Automobile interior and exterior parts
      • Appliances


      • Galvanized
      • Oxidized
      • Stainless Steel  
      • Aluminum
      • Brass
      • Copper

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