There are several types of this steel: Aogami #1, Aogami #2, and Aogami Super. Aogami #1 (Blue Steel No.1) has the highest carbon content (about 1.25–1.35%). Because of this, it can achieve maximum hardness and provides outstanding wear resistance. Aogami #2 (Blue Steel No.2) is regarded as the most balanced and popular variety. It contains a high amount of carbon (about 1.05–1.15%) and is alloyed with chromium and tungsten. Thanks to this, it is easier to sharpen. Aogami Super (Super Blue Steel) adds molybdenum and vanadium to the high-carbon base along with chromium and tungsten. These additional elements make Aogami Super famous for holding its edge for a very long time without dulling. It is considered a premium steel, combining the best qualities: exceptional sharpness, high hardness, and enhanced edge retention.
It is important to remember that knives made of Aogami steel require special care. As a carbon steel, it is prone to corrosion. Japanese knives made of Aogami should never be washed in a dishwasher. After each use, they should be hand-washed, dried thoroughly, and occasionally treated with camellia oil to protect against rust. Aogami knives are rightfully considered among the finest kitchen knives in the world.