Silicates are a group of minerals that contain silicon and oxygen, the two most abundant elements in the Earth's crust. They are the most common type of mineral, making up about 90% of the Earth's surface. Silicates can be found in various forms, including quartz, feldspar, and mica, and they play a crucial role in the formation of rocks and soils. These minerals are classified based on their structure and composition. For example, tectosilicates have a three-dimensional framework of silicate tetrahedra, which gives them unique properties. Silicates are not only important in geology but also have applications in industries such as ceramics, glass, and electronics.