Named for blue paper put on steel at Hitachi factory. Aogami (blue) steels are graded as Super, #1 and #2.. All made from same iron stock as Shirogami (white) steel, Aogami steels have high carbon (1.1-1.5%), .5% chromium for carbide formation and tungsten for edge life. Aogami Super has added vanadium for wear resistance.
Typically Aogami 2 is the toughest of the Aogamis. Aogami steels do not sharpen as easily as Shirogami, but they cut better as they dull.
Highly recommended for professionals that need a more dependable knife with good edge life. Aogami steels have little corrosion resistance and special attention is required to prevent rusting.