Super Glue fuming is good to use on what type of materials? (4)
-Leather -Plastic bags -Floor Tile -Metal
Which of the fingerprinting techniques produces a white-appearing latent print>
What substance can you substitute for ninhydrin if you need to?
What is most often used in conjunction with chemically induced fluorescence to visualize latent prints?
high intensity light sources
If you were trying to visualize latent prints? on leather and rough plastic what type of brush or brushes would be best to use?
Fiberglass brush or Camel hair brush
What would an investigator do next after successfully visualizing a latent print on an object?
take a 1 to 1 photo of the print
Fingerprint patterns which contains two or more patterns or a pattern not covered by other categories.
Systems which are designed to place fingerprints into computers so as to allow the comp. to categorize, compare a set of fingerprints.
Fingerprint patterns which do not have type lines, deltas, or cores.
The approximate center of a finger print patterns
The ridge point nearest a type line divergence
a reproduction of friction skin ridges on the palm side of the fingerprints and thumb
Fingerprints that are invisible to the eye
Fingerprints which must have one or more ridges entering one side of the print, recurving and exiting the same side.
ridge impressions left on soft material such as putty, wax, soap or dust
a loop which opens toward the thumb
the pattern area of a fingerprint surrounded by two diverging lines
a loop which opens towards the little finger
fingerprint part terns which must have type lines and a minimum of two deltas
3 fundamental principles of fingerprints (3)
-A fingerprint is an individual characteristic; no two fingerprint posses identical ridge characteristics -A fingerprint will remain unchanged during an individual's lifetime. -Fingerprints have general ridge patterns that permit them to be systematically classified
Explain how and why fingerprints are found on objects which have been touched?
Sweat and oil is constantly , secreted on to the surface of finger ridges. When skin comes in contact with a surface, these fluids are left behind the shape of a print.
put powder of the print, blow excess powder off and then place tape over the print, remove tape and place on a white card. (used often on nonporous surfaces such as glass, plastic, or metal.
-spray the area with the spray and then wait 24 hrs. -ninhydrin reacts with amino acids and yields a purple substance. -used on porous substances
-place paper with suspected print in a container which iodine crystals- iodine -fumes are absorbed by sweat and oil left behind and will give and orange-brown outline. -used on nonporous surface
Reacting with Silver Nitrate and exposing to ultra-violet light
-the surface of suspected print is sprayed with silver nitrate solution and then you will get a blackish-brown print. -It reacts with the salt in sweat when exposed with UV light -used with porous substances