Wednesday, August 26, 2009

Chemicals/tecniques used to develop fingerprints

When the surface is

Nonabsorbant(2 methods):
-Black powder-black carbon or charcoal for light sufaces
-Gray powder-aluminum dust for dark sufaces.

Porous(3 methods):
-Iodine fuming (has the ability to sublime)
-3% solution of silver nitrate
-0.6% ninhydrin powder dissolved in acetone or ethyl alcohol.

Hard(2 methods):
-Black powder-black carbon or charcoal for light sufaces
-Gray powder-aluminum dust for dark sufaces.

Smooth(3 methods):
-Iodine fuming (has the ability to sublime)
-3% solution of silver nitrate
-0.6% ninhydrin powder dissolved in acetone or ethyl alcohol.

The previous information was derived from:
http://www.bxscience.edu/publications/forensics/articles/fingerprinting/f-fing03.htm

2 comments:

  1. I like it how you were very descriptive about the Iodine fuming because I've heard of silver nitrate, and ninhydrin being used to develop fingerprints but I didn't know that they could be mixed.

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  2. Well I wasn't really saying they could be mixed; i was just listing different methods briefly. I don't belive they can be mixed. I'll change that...

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