Quote Originally Posted by Aimbot View Post
That's not really true. The Japanese Islands have very poor mineral resources. The folding process was done to remove impurities common to the native materials. It also helps to hold a sharper edge, but the durability is really not comparable to a traditional western longsword made with western steel, which was naturally superior. I might be mistaken, but I don't think I am.
I have a book on the subject, and the advantage in the folding process is combining two features. Western swords tend to be made out of either hard or soft steel. Hard holds a real good edge but is more brittle, better for something like a rapier. Soft is durable but doesn't hold its edge very well, but you need the durability for a big smashing claymore. A katana's folded steel allows for the benefits of both with a hard edge and soft core. (Relatively speaking metal is still metal)

That and the katana's shape allows for better slicing, but still is decent for thrusting.