High carbon steel is the best knife blade material. It is nearly indestructible, even when used to cut and chop food on metal or natural stone surfaces. It is easy to sharpen to a supreme cutting edge with a sharpening steel or other honing tools. Once sharpened, high carbon steel holds its edge well, even with repeated use.
Aesthetically speaking, carbon steel gets the lowest marks. It has no stain resistance and discolors immediately upon contact with acidic foods such as tomatoes, citrus fruits, wine or vinegar. Over time, the blade will turn totally black, although the discoloration does not adversely affect the knife's cutting ability or impart foods with odd tastes or colors. High carbon steel is also susceptible to rust and requires regular scouring with stainless steel pads to keep it clean and shiny.