Alkali feldspar is a group of rock-forming minerals that are primarily composed of potassium and sodium aluminum silicates. They are commonly found in igneous rocks such as granite and are essential in the formation of many types of rocks. Alkali feldspar is known for its distinctive crystal structure and can appear in various colors, including pink, white, and gray. These minerals play a crucial role in the geological processes of the Earth. They are not only important for understanding rock formation but also have applications in ceramics and glass production. The presence of alkali feldspar can influence the physical properties of rocks, making them significant in both geology and industry.