An example of mineralogy would be the study of quartz. Quartz is a common mineral found in many different types of rocks, such as granite and sandstone.
A mineralogist might study the properties of quartz, such as its chemical composition (SiO2), crystal structure, and physical properties such as hardness, refractive index, and specific gravity. They might also study the different varieties of quartz, such as clear rock crystal, amethyst, citrine, and rose quartz, and investigate the factors that give rise to the color variations.
In addition, a mineralogist might investigate the formation of quartz and the different environments in which it occurs, such as in igneous, metamorphic, and sedimentary rocks. They might also study the occurrence of quartz deposits in different parts of the world, such as the occurrence of large quartz veins in Brazil.
Finally, mineralogist also work in the field of industrial minerals, and contribute in the development and production of quartz used in ceramics, glass, and semiconductor industry.