Shirogami #1 (White Paper Steel #1) is one of the purest knife steels produced by Hitachi. Designed to minimize alloying elements, it contains primarily iron and carbon, allowing it to develop an extremely fine grain structure. This purity enables Shirogami #1 to take an extraordinarily sharp edge and makes sharpening remarkably easy compared to most modern steels. Because of its high carbon content, it can achieve very high hardness levels while maintaining excellent cutting feel. It is highly favored by traditional Japanese bladesmiths and professional chefs who prioritize ultimate sharpness over corrosion resistance. However, the lack of chromium makes it highly reactive and prone to rust if not properly maintained.
Comparable Steels:
Shirogami #1 > Shirogami #2 in hardness and edge retention
Shirogami #1 < Aogami #1 in wear resistance
Shirogami #1 < Aogami Super in edge retention
Shirogami #1 > 1095 in sharpening ease and edge refinement
Shirogami #1 ≈ 52100 in cutting performance, but offers easier sharpening
Shirogami #1 < CPM MagnaCut and M390 in corrosion resistance
Shirogami #1 remains one of the benchmark steels for achieving the finest possible cutting edge in traditional Japanese knife making.