10 Times Humanity Found the Answer (and Then Forgot)

Damascus Steel
The secrets of this neat-looking metal-making technology have been lost to history. Dmitry Chulov/iStock/Thinkstock

It's an old story: You're hanging out with your blacksmith, metallurgist and weapon-enthusiast friends and you've run out of things to argue about. Sure enough, someone brings up the legendary metal weapons once traded in medieval Damascus, famed for their supposedly irreproducible strength, edge and wave pattern. One friend hammers on about how "damascened" steel is no lost secret metal or technique, but merely a method of billet welding, in which different metals are fused, drawn and folded to create a wave pattern. Another defends to the hilt the view that these fabled blades were truly unique.

So who's right? Well, although we can make blades today that rival Damascus steel weapons, few would dispute that their plasticity, strength and keen edge were amazing for their day. Nor has anyone yet made blades with quite the same characteristics as the originals, even when starting with the same carbonized steel that the weapon masters of Damascus likely used [sources: Verhoeven et al., Wadsworth and Sherby].

The method for making Damascus steel blades was a closely guarded secret, like much of the armorer's art, and was lost when trade in the blades failed in the late 18th century. One theory holds that the art died when its source of iron in southern India, which perhaps produced ore peppered with key impurities like tungsten and vanadium, tapped out. Blacksmiths' legendary quenching liquids, rumored to range from urine to the bodies of slaves, long provided another possible explanation for the weapons' strength and edge-holding qualities. Today's theories, however, favor lost techniques of thermal cycling or low-temperature metalworking [sources: Sullivan, Verhoeven et al., Wadsworth and Sherby].

Either way, you can have damascened steel, but Damascus steel blades may well be unique items, like Stradivarius violins. And no one will ever crack that mystery ... right?