Strong and lighweight metal used for contrruction of airplanes.
Alluminum is probably the lightest of coinage metals used to-date.
The lightest 'non-metal' could be Hydrogen and Helium! Both are gases, and therefore, not a metal.
The lightest metal is lithium.
In the U.S., zinc is the lightest metal currently used. Cents are 97.5% zinc with only a small amount of copper plating. However worldwide, aluminum is the lightest metal used for coinage.
Lithium is the lightest.
Aluminum
It is the lightest metal used for batteries and is very efficient for walls.
lithium
Primarily aluminum and aluminum alloys.
Cobalt.
Helium