What The Heck Is Magnetic Fingerprint Powder?

Most people are familiar with the concept of fingerprint powders even if they have never used it or had it spread all over their home. It’s cheap, usually black, messy, and pretty hard to clean up. It works well though and most basic processing kits used by CSIs and patrol officers contain a jar. Aside from black it comes in a multitude of colors (made to contrast with various backgrounds) as well as fluorescent powders for use with an alternate light source. But there is another type of fingerprint powder you may not be aware of and we call it magna-powder. Magna-powders come in all the same colors as traditional powders but what makes them different is the presence of tiny magnetic flakes embedded with the powder.

Magnetic Fingerprint Wand. The magnet is on the left end and the plunger is on the right

Magna-powder is more expensive initially but it can pay for itself over it’s lifespan. What makes magna-powder advantageous at times is that the “brush” never contacts the evidence (as it does with a fiberglass brush) which may help with fragile prints. The photo above shows one type of “wand” that is used to apply the powder to the evidence. The tip of the wand houses a magnet that “attracts” the powder to the wand holding it in place while the analyst brushes the evidence. Another great aspect of the powder is that any unused powder can be collected with the wand and placed back in the jar for processing at a future date. The examiner just pulls up on the plunger at the other end of the wand which separates the magnet from the outer housing and the powder drops back into the jar. This makes for a more effective clean-up which any home owner would appreciate.

Developing fingerprints with magna-powder

Magna-powder can be used on a variety of surfaces but I have had the best luck on plastics (like credit cards and driver’s licenses). It can also be used on paper and I have had success using it on water soaked documents that have been dried (as in recovered from lakes). Obviously using it on ferrous metals or magnetized surfaces might pose some challenges.  There’s nothing particularly special about the powders but having your characters break out a jar might give your story that extra detail that others will miss. Certainly, any readers who are in law enforcement will recognize that you’ve done some homework by picking a powder few other authors talk about.

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About forensics4fiction

Hi there. Thank you for visiting my BLOG for crime writers. I hope you will find it interesting. I would love to hear your questions and thoughts regarding forensics and criminal investigations. I hope that the information here will help answer your questions or ignite your imagination. I am a retired senior criminalist with 15 years of forensic experience. I have served as the president of the Association for Crime Scene Reconstruction, Rocky Mountain Association of Bloodstain Pattern Analysts, and the Rocky Mountain Division of the International Association for Identification. I am triple board certified in forensic related fields and one of only 40 board-certified bloodstain pattern analysts and 80 board-certified footwear examiners worldwide In addition to writing over 60 scientific papers, I have worked as the editor of the Journal of the Association for Crime Scene Reconstruction, been interviewed by and consulted for television, books, magazines, and newspaper articles including documentaries on the Discovery Channel and National Geographic.

Posted on October 11, 2011, in The Crime Laboratory, The Crime Scene and tagged , , , , , , , , , , , , . Bookmark the permalink. Comments Off.

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