2025 ASEE Annual Conference & Exposition

Introductory materials science and engineering courses often focus on engineering materials, such as steels, technical ceramics, and polymers. For instance, the grain size of a metal is often measured and related to its strength and mechanical properties. However, natural materials often have similar microstructural features that can be used to broaden instruction and motivate students.

We have designed a laboratory module using geology specimens to teach error analysis and quantifying microstructures. This lab is implemented at the beginning of the term in an introductory Materials Science and Engineering course, so minimal technical knowledge of materials science is required. Prepared thin sections of geology samples are imaged using planar optical microscopy. Students measure feature sizes, repeating measurements in a single area and different sample regions. Students compare the reproducibility of measurements to variability within samples, to emphasize the multiple aspects of uncertainty that is reported in labs.

This work will provide specific information on the samples and background on the materials and equipment used, including pricing and suppliers. It will also provide insights into the types of geology specimens suitable for unpolarized, reflected light microscopy. This low-cost activity can be easily adapted for outreach or in-class activities.