654877bd_erials_Science_and_Engineering__Significance
[Date] 3500 BC (estimated) [Candidate Moment] Egyptians smelt iron (perhaps as a by-product of copper refining) for the first time, using tiny amounts mostly for ornamental or ceremonial purposes. [Significance] 
Unlocks the first processing secret of what will become the world's dominant metallurgical material.
Greatest Moments in Materials Science and Engineering
Significance