The typical composition of Earth's crust primarily includes oxygen (about 46.6%), followed by silicon (around 27.7%). Other significant elements include aluminum, iron, calcium, sodium, potassium, and magnesium. These elements combine to form various minerals, such as quartz, feldspar, and mica. The crust is primarily divided into two types: continental crust and oceanic crust, each with distinct properties. Understanding the crust's composition is essential for fields like geology and mineralogy, as it influences phenomena such as tectonic activity and resource distribution.