Although we can not see them, we know from certain meteorites (Nickel/Iron meteorites) and from the density measurements of the rocks we see at the Earth's surface compared to the mass of the whole planet that the two most abundant elements in the Earth's core must be Iron and Nickel. Iron being the predominant of the two.
It makes up the majority of the molten core of the earth.
Iron is the most abundant metal in the inner and outer core of the Earth.
Oxygen is the most abundant element in Earth's lithosphere, comprising about 45% of its mass.
The earths outer core's most abundant elemant is silicon. :)
The most abundant element in both the Earth's inner core and outer core is iron. It makes up about 85% of the Earth's core composition.
The element that makes up most of the earths CORE is iron.
The second most abundant element in the Earth's crust is silicon, comprising 27.8% of the crust by mass.
silicon
Aluminum 7.5 to 8.1%
Siliconsilicon at 28%silicon!
The most abundant metal in the Earth's crust is iron. The most abundant element in the Earth's core is oxygen.
That would be silicon, or SiO2