Which mineral is the most abundant in Earth's crust?

Feldspars are a group of rock-forming minerals that make up a large share of Earth’s crust, commonly estimated at roughly 50 percent by volume when both alkali feldspar and plagioclase are included. They are found in many igneous, metamorphic, and sedimentary rocks. Feldspars are important in geology because they are so widespread and help identify rock types. They are also used in ceramics and glassmaking.