What is the primary component of the Earth's crust?

The primary component of the Earth's crust is oxygen, which combines with other elements to form a variety of minerals that make up the rocks in the crust. Oxygen is the most abundant element in the Earth's crust by weight, comprising about 46% of the crust's composition. Most commonly, it is found in silicate minerals, where it chemically bonds with silicon, aluminum, and other metals to form common rock types such as granite and basalt.

Silicon is also a significant component, but it typically pairs with oxygen to form silicates. While iron and aluminum are present in the crust, they do not make up as large a proportion as oxygen does. Since oxygen plays a fundamental role in the mineral composition of the crust, understanding this is essential for studying geological processes and the composition of terrestrial environments.