The crust is made out of Silicon, Oxygen and magnesium, The mantle is mainly made out of silicates like iron nickel silicone, oxygen. The core is made out of iron and nickel.
The earths layers Crust, Upper mantle, Lower Mantle, Outer Core, Inner core
The layers density keeps layers that are supposed to be liquid into solid layers
Solid crust, Solid 1mantle and a liquid inner core