There's been many Japanese fantasy sword lore given in JRPG, anime, etc about fantasy swords. This one appears to be stranger than fiction.
A Katana forged from ore completely from a meteorite by famous Japanese swordsmith, Yoshindo Yoshiwara.
Now we wait for 1000 years when the end of time demon comes and a hero emerges with the Chrono Trigger and saves us all.
Katana Forged from Meteorite: The Sword of Heaven
Back in 2010 we heard about how the late Sir Terry Pratchett made his own sword using a bit of iron from a meteorite. The blade of this katana on the other hand was made entirely from a meteorite. It’s called the Tentetsutou (天鉄刀), which translates to Sword of Heaven.