Iliac crest pain is not that common in the general population, but it is frequent in older individuals, runners (and athletes in general), lower back pain sufferersâ¦ But that doesn`t mean âregularâ people like you and me can`t experience it from time to time!
The mantle is composed of iron-magnesium silicates, and the crust is composed of roughly 5 percent iron. All together, iron makes up an estimated 35 percent of the Earth's mass. Oxygen. Oxygen, the second most abundant element on Earth, is found mainly in the crust.
The Crust is the thinnest layer in the earth. The Mantle is very massive (huge) if you don't get huge imagine it takes up 80% of the earth now that is huge. The outer core is made of iron and nickel. The inner core is the most inner layer it is very solid.