Oxygen is the most abundant element in the Earth’s crust. It is a vital component of rocks, minerals, and soil, primarily found in the form of oxides and silicates. The rarest elements in the crust are not the heaviest, but are rather the siderophile elements (iron-loving) in the Goldschmidt classification of elements. These have been depleted by being relocated deeper into the Earth's core; their abundance in meteoroids is higher. Earth’s Crust Elements The crust is a rigid surface containing both the oceans and landmasses. Most elements are found in only trace amounts within the Earth’s crust, but several are abundant. The Earth’s crust comprises about 95% igneous and metamorphic rocks, 4% shale, 0.75% sandstone, and 0.25% limestone. Silicon is second most abundant element in the Earth's crust, and accounts for 28% of the crust’s mass. Silicon is an essential material in the manufacture of electronics and computer chips.
