Deer, Dog

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Deer, Dog Muskrat hair
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Which is Caucasian, Negroid, Mongoloid?
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Pulled Hair v. Shed Hair
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Razor, cut hair Split hair
5
Human eyebrow
6
Burned hair
7
Buckling of hair
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Hair match

• This is the view that a comparison scope can give
  when comparing two matching hairs

9
Medullary Index of Hair

• To find the MI
• Diameter of medulla/hair shaft diameter
• Humans lt1/3
• Other animals gt1/2
• Classify Medulla as
• Continuous, Interrupted, Fragmented, or Absent

10
Fibers
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Types of fibers

• Natural fibers
• Animal fibers are most common at crime scene
• Man-made

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Natural fibers

• Animal
• Wool from sheep most common
• Goats, camel, alpaca, rabbit, mink, llamas,
  beaver
• Plant
• Cotton most common
• Flax (linen), ramie, sisal, jute, hemp
• Excrement
• Silk from silkworm (cellulose from mulberry
  leaves)
• Mineral
• Asbestos

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Cotton fibers cross-section
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Flax Fibers
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Hemp fibers
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Silk fibers

• Raw thrown
• Wild silk

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Asbestos fibers
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Man-Made fibers

• Regenerated fibers
• Machine made from natural materials like cotton
  or wood
• 1910 rayon, then acetate, then triacetate
• Synthetic fibers
• Most fibers are made synthetically from chemicals
• 1939 nylon, then polyester and acrylic
• Shape or cross-section can determine value of the
  fiber manufacturer specific

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Acetate Fibers
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Nylon fibers
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Orlon Fibers
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Polypropylene fibers