The Earth has four layers.
First is the crust, it is made up of 46% oxygen, 28% silicon, 8% aluminum, 6% iron, 4% magnesium, 2.4% calcium and 5.6% of other chemicals.
The Mantle is composed of 44% oxygen, 21% silicon, 22.8% magnesium, 6.3% iron, 2.5% calcium and 2.4% aluminum.
The Outter Core is 85% iron, 5%nickel, 5% sulfur and 5% oxygen.
The Inner Core of the Earth is 94% iron and 6% nickel.