ILLUMINATING THE GEOSCIENCES AND OTHER STEM FIELDS WITH OPTICAL MINERALOGY

Many geoscience college programs are consolidating mineralogy and petrology courses into singular “earth materials” courses, and some cut the in-depth content on optical mineralogy. Optical Mineralogy studies how light interacts within minerals. Many geoscientists are familiar with identifying minerals by a few optical properties in prepared rock thin sections. Analyzing the optical properties of minerals prepared as grain mounts and spindle stage mounts in refractive index liquids becoming more of a lost art yet are quick to prep and relatively low cost compared to thin sections. The established field of optical mineralogy and crystallography can illuminate so much more about a mineral’s properties and crystallization history through a comprehensive analysis of a mineral’s optical properties.

As minerals are three-dimensional materials, a comprehensive analysis of the optical properties of mineral grains in refractive index liquids can advance one’s understanding of a mineral’s chemistry and structure in multiple dimensions. Grain mounts and spindle stage mounts of minerals also help with grasping 3-dimensional concepts, such as stereographic projections, which are necessary for other geoscience disciplines like structural geology. Optical characterization can complement and/or guide other analytical techniques. Analysis of mineral’s optical properties are additionally key in several job industries such as entry level analytical laboratory jobs, environmental testing, pharmaceuticals, medical testing, and the mining industry. Experience in collecting and analyzing optical mineralogy and crystallography data can foster good spatial reasoning, laboratory techniques in multiple STEM disciplines, and understanding in difference in a mineral’s properties across dimensions.