Today in class we moved on to the next phase of our forensics investigation: ink chromatography. The basic idea is that it can be useful to find out the specific brand of pen or marker that a criminal used. For example, if the police figured out that Hitler’s famous diary was written in ink that was only a few years old, they might be able to determine that the document was a forgery. In fact, this was exactly what happened in the 1980s with the famous Forged Hitler Diaries.
In our lab today, students tried to determine which brand of black marker the hacker used. By exposing samples of ink to a mixture of water and rubbing alcohol, we were able to observe that the ink that was used had a high retention factor and was actually made of a combination of blue ink, green ink, and other dark colors.
We then tested five different brands of black marker (Expo, Sharpie, Crayola, Vis-a-Vis, and Office Supplies) to see if any of those common brands matched the type of ink that was used by the hacker. Most groups concluded that the marker used was a Crayola, although a few students thought it may have actually been a Vis-a-Vis.