Lithosphere

The lithosphere is the top part of the mantle while also being split up in between Earth's crust. The lithosphere has a chemistry composition far different from the planet as a whole. The lithosphere has tons of iron much like the mantle, but has more iron and magnesium contents and far lower aluminum, sodium, and potassium contents. In the lithosphere, the rocks are colder, harder, and more rough than the asthenosphere. It is rock strength that differentiates the lithosphere from the asthenosphere. The differences in strength between rock in the lithosphere and rock in the asthenosphere is a difference of temperature and pressure.