This is considered the foundation block for a study in geology. The theme covers broadly the composition of the earth and how these components are related. Mineralogy is a subset of geology specializing in the scientific study of mineral chemistry, crystal structure, and physical properties of minerals. Specific studies within mineralogy include the processes of mineral origin and formation, their classification, their geographical distribution, as well as their utilization. Petrography is a branch of geology that focuses on detailed descriptions of rocks. It involves a detailed analysis of minerals by optical mineralogy in thin sections under a microscope. Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the earth’s crust composition.