- 1). Look at the samurai sword blade for any visible grain, or hada. This grain is a sign that the sword was hand forged. Keep in mind that this only means it was handmade and is not indicative of its age.
- 2). Place a magnifying glass along the tempering line, or hamon. The tempering line of a true samurai sword will be made up of tiny dots with no fuzziness or haze as it would be on a machine-tempered line. Check with the magnifying glass around the base of the blade or the handle for a serial number, as this is a sign that it was machine made.
- 3). Check the metal of the blade. Most replicas and modern swords will be made of aluminum; real samurai swords are strictly steel. Place a magnet to the blade. You want it to stick to the blade.
- 4). Talk with experts and ask questions about a blade and its history when buying.
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