Damascus

I did want to lay to rest some of the Damascus Steel rumors that I've heard. First off, lets say what Damascus is. Damascus steel is only called Damascus because that is where the Crusaders first saw swords and knives that had a watery pattern in the blades. This was originally called "wootz" steel and was manufactured in India, where you can still see the remains of many forges built to face monsoon winds. The exact process to make true wootz was lost, though some French scientist (at least I think he was French) found a way to produce a reasonable facsimile. By taking steel and melting it down and adding a substance with sufficient carbon (like charcoal) to the liquid, the carbon would combine with the steel in the crucible. Then they'd pour it out and wait for it to solidify in little buttons of wootz, which they'd forge into billets (bars). By folding the metal over on itself the metal would form a wavy, watery pattern due to the two differing levels of carbonated metal. The fewer folds the more the pattern was pronounced, the more folds the lesser you would be able to see unless you were up close.
This part is where the legends came in. The folding process, which is called pattern forge welding, was originally done to purify the metal. By folding the metal and drawing it back out, you could work the impurities out of the metal. Now-a-days even the most garbage piece of rebar is of better quality steel than most of the middle ages swords. However, you still hear stories of swords that were folded 10,000 times and can cut through other swords. Metal will always retain the same qualities, so unless that metal could cut through another sword with only 1 fold, it can't do it with a million. By the way, here is a math fact for you. How many folds does it take to make a sword or a knife with 1,000,000 layers? Observe:

Fold 1 = 2 layers
Fold 2 = 4 layers
Fold 3 = 8 layers
Fold 4 = 16 layers
and so on until
Fold 20 = 1,048,576 layers of metal

So you see, it really wouldn't be impossible to create a piece of that complexity.

After the metal has been forged into the desired shape, edged, and polished, it would be dipped in an acidic bath that would react differently between the two levels of carbon in the metal, darkening one and shining the other. Some have also found a way to make Damascusized steel by using cable. Here is a pic.


And that is Damascus Steel.