High carbon steel is specifically developed for tools and knives. This one has highest wear resistance and lowest toughness. Very good steel and a very popular choice for high end Japanese kitchen knives. A lot of Japanese custom makers use it. Easy to sharpen, even high hardness. Edge holding is just outstanding. Original Japanese knives made from these materials are treated with non-corrosive, food-safe oils (e.g. camellia oil) to prevent oxidation.