In surah al-Hadiid  verse 20 explained how people spend their age/life in the world. Mostly they are only concerned with worldly affairs for the sake of greatness/splendor and pride of many assets
In surah al-Hadiid  verse 25 informed that Allah swt created iron [al hadiid] which is very beneficial to humans.
^^ When humans began to recognize the iron?
^^ In the context of archaeological finds, what civilization had firstly used the iron?