"Level Two" Friction Ridge Features
Key to 'Level Two' Friction Ridge Features:
- Ridge endings - Red " O "
- Bifurcations - Blue " [ ] "
- Dots - Gold " ( ) "
Details of friction ridge formation are collectively called a variety of terms including 'minutiae,' 'points' and 'ridge characteristics'. Some have taken the view that there exist up to seven different terms for friction ridge features. Others take the view that there exist three kinds of friction ridge features, and that the remaining minutiae are actually combinations of the three.
A Bifurcation is a friction ridge feature where a single friction ridge branches into two ridges. The angle, or the concavity, formed by the branching ridges is studied further in Level 3 analysis.
A Dot is a small friction ridge feature of a short length that typically contains a single sweat pore. To be considered a true Dot, the structure would have to appear to be as thick and heavy as the other friction ridges in it's immediate surrounding. If the feature has a length that is three times it's width, it can then be considered to be a 'short ridge', and not a Dot. The irregularities along the periphery of dots, and their internal structure are examined further in Level 3 analysis.
A Ridge Ending is a friction ridge feature where a single friction ridge makes an abrupt stop. This is not to be confused with friction ridges whose courses are interrupted by thin crevaces. These fissures are not considered to be true ridge endings. The terminus of a ridge ending may exhibit a blunt or a pointed structure. Further examination of this property is explored in Level 3 analysis.
Factors such as pressure and distortion may change the appearance of, or may create an 'artifact' amongst, some friction ridge features (see Distortion page). A friction ridge feature that appears as a bifurcation in the known print may appear as a ridge ending in the latent print. The examiner must undertake an assessment of the area of friction ridge impression to determine if the cause of the apparent discrepancy is attributable to Distortion. The use of techniques such as ridge counting and ridge tracing performed with respect to other friction ridge formations in the immediate vicinity is helpful to understand the cause and nature of the dissimilarity. If distortion is the cause of the discrepancy, then the presence of an 'artifact' would be within an examiner's tolerance for differences.
A Bifurcation is a friction ridge feature where a single friction ridge branches into two ridges. The angle, or the concavity, formed by the branching ridges is studied further in Level 3 analysis.
A Dot is a small friction ridge feature of a short length that typically contains a single sweat pore. To be considered a true Dot, the structure would have to appear to be as thick and heavy as the other friction ridges in it's immediate surrounding. If the feature has a length that is three times it's width, it can then be considered to be a 'short ridge', and not a Dot. The irregularities along the periphery of dots, and their internal structure are examined further in Level 3 analysis.
A Ridge Ending is a friction ridge feature where a single friction ridge makes an abrupt stop. This is not to be confused with friction ridges whose courses are interrupted by thin crevaces. These fissures are not considered to be true ridge endings. The terminus of a ridge ending may exhibit a blunt or a pointed structure. Further examination of this property is explored in Level 3 analysis.
Factors such as pressure and distortion may change the appearance of, or may create an 'artifact' amongst, some friction ridge features (see Distortion page). A friction ridge feature that appears as a bifurcation in the known print may appear as a ridge ending in the latent print. The examiner must undertake an assessment of the area of friction ridge impression to determine if the cause of the apparent discrepancy is attributable to Distortion. The use of techniques such as ridge counting and ridge tracing performed with respect to other friction ridge formations in the immediate vicinity is helpful to understand the cause and nature of the dissimilarity. If distortion is the cause of the discrepancy, then the presence of an 'artifact' would be within an examiner's tolerance for differences.
"Level Two" Friction Ridge Detail
Friction ridge features generally referred to as 'Minutiae' and 'Points,' and their morphology (size and shape) are regarded as "Level Two" detail.
"Level Two" friction ridge features begin during the early stages of fetal life, and are subject to a myriad of epidermal configurations, differential growth, and alignment factors that result in unique and distinguishing arrangements of 'Level Two' detail for each and every person born. Research conducted since the 1800's has established that the stressors in growth affecting the friction skin formations is so varied, that the "Principle of Uniqueness" of fingerprints is certain.
For correspondence between the latent print and the known print, the "Level Two" detail would be in agreement in the same area in both impressions in their A.) shape, B.) location, C.) orientation, and D.) group (spatial) relationship, with no genuine dissimilarity in their appearance or arrangement.
"Level Two" detail is used in conjunction with 'Level One' detail to formulate an Individualization. Exclusions can be effected using "Level Two" detail in conjunction with "Level One" detail.
"Level Two" friction ridge features begin during the early stages of fetal life, and are subject to a myriad of epidermal configurations, differential growth, and alignment factors that result in unique and distinguishing arrangements of 'Level Two' detail for each and every person born. Research conducted since the 1800's has established that the stressors in growth affecting the friction skin formations is so varied, that the "Principle of Uniqueness" of fingerprints is certain.
For correspondence between the latent print and the known print, the "Level Two" detail would be in agreement in the same area in both impressions in their A.) shape, B.) location, C.) orientation, and D.) group (spatial) relationship, with no genuine dissimilarity in their appearance or arrangement.
"Level Two" detail is used in conjunction with 'Level One' detail to formulate an Individualization. Exclusions can be effected using "Level Two" detail in conjunction with "Level One" detail.