A class of minerals that have the silicon-oxygen tetrahedron as their basic structure. They are further subdivided into subclasses based on the type of grouping of the silicon-oxygen tetrahedral (e.g. single chain, sheets, 3D framework, etc.). Silicates are the most abundant minerals in the Earth's crust and represent 95% of the volume of the crust. More than half of the 22 minerals that will be systematically studied in the lab portion of this course are silicates.