Blue Steel #1 is similar to Blue Steel No.2, but the additional Carbon and Tungsten / Wolfram result in even better edge retention and toughness. The steel is perhaps most commonly seen in high-grade Japanese traditional single-bevel edged knives.

Kurouchi Finish, the unprocessed (black) part on the top side of the blade has already developed a dark patina, which protects the blade and gives it a traditional Japanese look.