Unsolved mysteries of our planet

10. The earth consists of iron, oxygen and silicon
If we wanted to split the planet in composition, it would look like this: and 32.1 % iron, 30.1% of oxygen, 15.1 percent silicon and 13.9 % magnesium. It is believed that large proportion of iron (about 90 %) is in the kernel. And most of the oxygen in the earth’s crust (around 47 %).