What aspect of tools leaves distinct marks on surfaces?

The distinct marks left by tools on surfaces primarily result from their working edges. These edges can vary significantly between different tools and are designed specifically for cutting, scraping, or impacting surfaces. As a tool interacts with a material, the shape and sharpness of its working edges create unique impressions or marks that can be traced back to that specific tool. This can be incredibly useful in forensic investigations, as these marks can provide valuable evidence linking a tool to a crime scene.

While material composition and design features can also influence how marks are made, it is the working edges that directly contact surfaces during use and leave behind identifiable patterns. Color patterns do not typically contribute to the leave-behind marks and are often less relevant in forensic contexts. Understanding the significance of working edges helps in identifying tools based on the marks they leave behind, which can play a crucial role in criminal investigations.