Japanese sword makers used tamahagane steel
developed in Japan in the 4th Century B.C. A traditional Japanese sword is not made from Damascus steel! Damascus steel is a nickname for Wootz steel
, likely originally developed in S. India 6th Century B.C. and imported by Arab traders to Damascus by the 3rd Century B.C. The steel production technique was lost at some point when trade routes were cut off, and eventually rediscovered and popularized as Damascus steel in the early 1970's at gun shows, and this reborn steel eventually made its way into the hosts of some modern torches. I am not any expert, just read wikipedia sometimes, but I am unaware of any sort of fake Damascus steel, other than distinguishing between material used in authentic Damascus blades and the modern equivalent of producing that steel. IOW, as crazy as its desire makes us, that Damascus host is surely sincerely genuine.
Good information there. I'll just add what little I remember from my metallurgy text from 30 years ago. Whatever name we call it by, the samurai swords were made of two different types of steel, one harder, and one softer, hammered together, and then folded over and hammered again many times to create the many layers. This accomplished two things, the sandwiched steel blade was very flexible and hard to break, and the hammer welding process acted to express impurities like sulphur that would compromise the strength of the steel.
The forge used to make the steel was actually invented in, and imported from, Mongolia, and although pretty good for the time, it didn't get hot enough like a modern Bessemer furnace so that the slag impurities would just float to the top where it could be skimmed off. It didn't help that the iron ore the Japanese had actually wasn't that great a quality, which was another reason for the labor intensive forging process.
By contrast, most modern layered "Damascus" (as opposed to etched Damascus) is produced by a hydraulic two-ton trip hammer which eliminates the arduous manual forging process. They can even make stainless steel layered Damascus which wouldn't have been possible for the Japanese smiths because they couldn't have made the chromium steel, which requires a modern electric furnace, which was only invented in the 20th century and gets even hotter than the original Bessemer furnace, but more importantly allows more precise control of the melt which is necessary for producing alloy steels like stainless. (Ordinary steel just contains iron and small amounts of manganese, with the addition of carbon in the case of carbon steel).
By the way, this layered steel wasn't just made in Japan; although their weapons are probably the most famous example of this process. It was also done in Indonesia, where examples exist of blades made from nickel iron meteorites. These are interesting in that they contain the minerals taenite and kamacite, two nickel-iron minerals which don't occur on earth.