# Why Fe 3+ is more common than Fe 2+

I heard that $\ce{Fe}(\mathrm{III})$ is more common than $\ce{Fe}(\mathrm{II})$ but I've not heard a very clear explanation. Could someone please explain this incorporating electron configurations in their answer?

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The electron configuration of $\ce{Fe(II)}$ is $1s^22s^22p^6 3s^23p^6 3d^6$.
The electron configuration of $\ce{Fe(III)}$ is $1s^22s^22p^6 3s^23p^6 3d^5$.
The half filled orbital $3d$ is more stable than the same orbital filled with 6 electrons. So, $\ce{Fe(III)}$ ion is more common than $\ce{Fe(II)}$.