Quick breakdown of what costs money:
Labour and skill of the smith: A hand forged sword made by a master bladesmith takes a lot longer to crank out then a factory Like Hanwei.
The polish: The polish is what makes the difference in a sword. Its extremly labour intensive and the difference between a good and a mediocre polish is hard to tell with an untrained eye. Polishers can cost $100 per inch of blade and more.
The handle/tsuka materials and fittings: Copper costs less then Gold or silver, cotton Ito cost less then silk, There is different grades of Same (rayskin). Some parts are mass produced and some are origional hand crafted pieces.
At the end of the day you could well prefer the handling charistics of a Practical katana over a 15000 dollar Nihonto (traditionally made japanese katana) but what makes the difference in proice is the "little" things and asthetics. An katana is a work of art, not just a killing tool, you paty for the art and teh skill and materials it takes to create that art.
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