The Miracle Of Iron !!

[Darwinian]

It may be that the reason the Qu'ran says that iron was 'sent down' to the Earth is because at that time people knew that occasionally rocks (meteors) fell from the sky and many of these would be primarily composed of iron. To people who simply knew nothing about the formation of the Earth or the solar system it would probably seem quite rational to assume that this is where iron comes from.

And if your name is Muhammed and you are creating a new religion to give you power over the masses then why not use this as example of Allah's power, sending iron to the Earth.