is mainly made of four elements: iron, oxygen, silicon and magnesium that make up more than 90% of the earth’s mass.

The earth is composed mostly of iron (32%), oxygen (30%), silicon (15%) and magnesium (14%).

There are other elements such as sulfur (3%), nickel (2%), calcium (1.5%) and aluminium (1.5%), with the remaining 1% consisting of trace amounts of other elements.

Earth’s atmosphere is nitrogen (78%), oxygen (21%), argon (0.9%), and carbon dioxide (0.03%) with very small percentages of other elements.

Earth’s crust is made up of oxygen (47%), silicon (27%), aluminum (8%), iron (5%), calcium (4%), and magnesium, potassium and sodium (2%).

Earth’s mantle is composed mostly of silicate rocks rich in magnesium and iron.

Earth has a solid, inner core of iron surrounded by a liquid, outer core composed of a nickel-iron alloy.