Why is the boiling point of iron higher than magnesium ?

Firstly, we have to know that Iron and Magnesium are metals; so what differs the boiling point of a metal to another?!!! Boiling point of any metal depends on the hardness of this metal, as hardness increases, boiling point increases, for example, boiling point of aluminum is higher than that of Magnesium is higher than that of Sodium. Generally, boiling point depends on the number of that metal has, as this number increases, the strength of metallic bond between metal atoms increases, hardness increases, and boiling point increases.. For your knowledge, Iron is a transition metal, and these metals are known of availability of and have a higher melting and boiling points...