Tool Marks: Identifying Unique Patterns

Which of the items is not likely to show an identifiable tool mark?

a. A bone knife missing a chip in its blade

b. A decades-old hammer used frequently in a workshop

c. A custom-made serving fork

d. A lug wrench sold at several auto shops

Answer:

The item not likely to show identifiable tool marks is a lug wrench sold at several auto shops because it's a mass-produced item and doesn't possess independent, unique features.

When we talk about tool marks, we are referring to the unique marks left behind when a tool comes into contact with an object. These can be intimately associated with the unique characteristics or defects on the specific tool. In this case, a bone knife missing a chip in its blade (option a) would likely leave a unique marking due to the missing chip. A frequently used decades-old hammer (option b) would have been worn and reshaped over time, which would create identifiable marks when used. A custom-made serving fork (option c) would also likely be unique and therefore leave identifiable tool marks.

However, a lug wrench sold at several auto shops (option d) is mass-produced, and therefore doesn’t possess unique, independent features that could create identifiable tool marks.

It's important to note that this consideration applies to a pristine, unmodified lug wrench directly from the store. If the wrench had been altered or damaged in any way that made it unique, then it could hypothetically leave identifiable marks.