When investigators discovered three deceased victims at a vehicle crash site over the side of Backbone Mountain they retraced the vehicle’s path and also discovered several pieces of broken glass lying in the roadway. In this lab, students will examine the refractive index of various glass fragments. They will learn the importance of glass analysis in the forensic field and how this analysis is performed by forensic scientists. In addition, students will learn to microscopically determine the refractive indices of several known types of glass, and then apply what they have learned in the comparison of glass fragments collected from a crime scene to a potential source.

Supplies are included for up to 30 students working in six groups. As in all Lyle and Louise modules, this kit is geared to high school and undergraduate courses and is matched to National Science Education Standards. Kit includes microscope slides, microscope coverslips, refractive index liquid 1: nD=1.45 (1 Set of 6 Bottles), refractive index liquid 2: nD=1.47 (1 Set of 6 Bottles), refractive index liquid 3: nD=1.49 (1 Set of 6 Bottles). Also includes headlight reference glass (6 envelopes), bottle reference glass (6 envelopes), evidence questioned glass (6 envelopes), evidence known glass (6 envelopes). It can be stored at room temperature.