> For example, in parts of Iliad bronze is given as a valuable gift. In other parts, it’s thrown away on the heads of spears and arrows. So was it composed before or after the fall of the Bronze Age?

I'm confused by what paradox do you see there - the most useful metal you can get always gets put on spears and arrows, it's not "throwing things away", it's the most important usage for high quality metal, and it is a valuable gift exactly because it allows you to make more or better spearheads and arrowheads. What would they be saving for otherwise? Shovels are important, but your spear is literally a matter of life and death and does get priority.

Also, it's not generally destroyed or discarded, all the valuable stuff does get picked up from battlefield afterwards.