I Includes the physical and chemical analysis of

A. Techniques used 1. Chemical and physical analysis, and photography B. Types of Analysis

b. Different papers exhibit different properties -different colors -different weights -some fluoresce under ultra-violet

c. Watermark -translucent mark placed on paper by the manufacturer - can establish approximate

2. Ink a. Colored liquids composed of a number of substances in a solvent

3. Pencils a. “lead” in pencils is a mixture of graphite, clay and kaolin

4. Typewriter a. Type is compared to the FBI Typewriter Standard Files b. Make

II. Document forgeries A. Involves 1. Forging a signature 2. Erasing a statement and

B. Determining authorship 1. Handwriting analysis is the product of 2 things a. physical

2. Forgery by tracing – there will be a lack of smoothness to the

C. Erasures - Two types 1. Mechanical erasures a. accomplished by rubbing the ink

2. Chemical erasures a. accomplished by using chemicals that bond with the ink and

D. Invisible inks (secret message) 1. Use organic liquids (milk, lemon juice) and heat

Videos https: //www. youtube. com/watch? v=m. XFjwih. UO 00 https: //www. youtube. com/watch? v=NN

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I. Includes the physical and chemical analysis of writing materials

A. Techniques used 1. Chemical and physical analysis, and photography B. Types of Analysis 1. Paper a. Can be prepared with a variety of raw materials - textures can be different https: //www. youtube. com/watch? v=ff. Uh. P 4 pig. J 4

b. Different papers exhibit different properties -different colors -different weights -some fluoresce under ultra-violet light

c. Watermark -translucent mark placed on paper by the manufacturer - can establish approximate age of document and possible location of store

2. Ink a. Colored liquids composed of a number of substances in a solvent b. Not easy to trace a pen, but easy to identify the ink c. Chromatography is used d. Age of the ink can sometimes be determined https: //www. youtube. com/watch? v=Fypi 6 d AJB 8 E

3. Pencils a. “lead” in pencils is a mixture of graphite, clay and kaolin b. More graphite = softer pencil, more clay=harder pencil c. Examination of marks can determine pencil “softness” and order of marks made

4. Typewriter a. Type is compared to the FBI Typewriter Standard Files b. Make and model of machine can be determined

II. Document forgeries A. Involves 1. Forging a signature 2. Erasing a statement and replacing it with another 3. Adding words to what is already there

B. Determining authorship 1. Handwriting analysis is the product of 2 things a. physical movement of the hand b. subconscious activity of the mind directing the hand

2. Forgery by tracing – there will be a lack of smoothness to the lines 3. Also need to note techniques, for example: - size of letters in relation to each other - spacing -slant and curves of the letters

C. Erasures - Two types 1. Mechanical erasures a. accomplished by rubbing the ink or pencil mark with an abrasive substance b. can be indicated by iodine fuming but the words will not show

2. Chemical erasures a. accomplished by using chemicals that bond with the ink and make them colorless b. still visible under ultraviolet light

D. Invisible inks (secret message) 1. Use organic liquids (milk, lemon juice) and heat paper gently 2. Chemical solutions that are colorless until treated with a second chemical 3. Chemicals that are colorless under normal light but show up under ultraviolet light

Videos https: //www. youtube. com/watch? v=m. XFjwih. UO 00 https: //www. youtube. com/watch? v=NN 1 QAC 8 lgw 8