Blue steel #2
Aogami No.2 (Hitachi Metals Ltd.) is made by adding Chromium and Tungsten / Wolfram to Shirogami No.2. This results in increased toughness and the production of hard carbide molecules which improve edge retention. Many knife users have noted that while Aogami No.2 is very similar to Shirogami No.2 in terms of edge sharpness, it has slightly superior edge retention.