The most abundant metal on Earth is aluminum. Aluminum is the third most abundant element in the Earth's crust, and makes up 8 percent of it by parts per million.
The most abundant metal inside the Earth is iron. Iron makes up to 34 percent of the Earth's mass, but is only the fourth most abundant element in the crust. Iron makes up 5 percent of the Earth's crust and 70 percent of the Earth's core. Aluminum, although more abundant in the crust and a constituent part of almost all terrestrial rocks, is much lighter than iron and cannot compete with it in terms of abundance by mass; however, it is more abundant in terms of surface availability and number of actual atoms.