Earths crust mineral composition are silicon oxide (SiO2),Magnesium monoxide (MgO),Ferrous oxide(FeO),Calcium monoxide (CaO),Sodium dioxide(Na2O) ,Potassium dioxide(K2O), while the Earths crust are sodium,magnesium,potassium,calcium,iron,aluminum,silicon,and oxygen .Because Earth is based on chemical composition and split up into a crust,mantle,outer core and inner core.