NCJ Number
226556
Journal
Journal of Forensic Sciences Volume: 54 Issue: 2 Dated: March 2009 Pages: 353-358
Date Published
March 2009
Length
6 pages
Annotation
This paper describes techniques for the conditioning and proper use of jewelry modeling wax in the production of tool mark standards.
Abstract
In crimes that involve the possible use of tools and/or the presence of tool marks, a complete study and evaluation of the questioned tool marks must be conducted in order to determine how the marks were most likely produced. All the information collected during the preliminary examination of the questioned tool marks should be used for making the comparison standards with the exemplar tool. Data on the possible angles, direction, and working area of the tool must be included when creating the comparison standards. When preparing to make tool mark standards with a suspected tool, a suitable variety of modeling wax should be selected. Jewelry modeling waxes come in many shapes, sizes, flexibilities, and rigidities. A table is provided to show the features of various commercially availably jewelry waxes and the types of tools for which each wax is best suited. After an appropriate piece of modeling wax is selected and the tool mark standards are prepared, excess wax is removed as necessary both prior to and after making the tool marks. Next, any veil of wax that obscures the tool mark standards is removed by treatment with a solvent as necessary. Finally, each tool mark standard is marked for identification. The replicas obtained are accurate, highly detailed, and 1:1 negative copies of the exemplar tool’s working surface. The replicas reveal in detail the class characteristics, wear patterns, damage, and accidental markings present on a tool’s surface. The authors are currently conducting several statistical studies for tool mark comparisons using the impression methods described in this paper. 1 table, 16 figures, and 25 references