Carbon Steel Knives

Carbon Steel Knives are extremely sharp, but have the reputation of being high maintenance since they can rust if proper care is not taken. You may think these knives are only suitable for professional chefs who know how to properly maintain the knives, but caring for them is actually quite simple. Just wash the knife immediately after use, and dry with a gentle cloth. It is highly recommended to apply some cooking oil for a protective finish as well. That is really all it takes to enjoy the finest carbon steel knives from Japan!

We know that knife descriptions can be confusing and loaded with complicated terms. In order to give you a firm understanding of carbon steel materials, we’ve compiled the basics below:

Colors: White, Blue, and Yellow

White, Blue, and Yellow are the names of the carbon steel materials made by Japanese steelmaker Hitachi. They are just brand names, so "blue steel" is not literally a blue color. In addition to White, Blue, and Yellow, you may hear about “Silver” steel (such as GIN-SAN). Silver steel has high carbon content, but belongs to the stainless steel category.


Japan Steel (NIHON-KO)

This is the most commonly used carbon steel material for kitchen knives in Japan. Affordable price is its selling point. Good for entry level chefs and home cooks.

  • NIHON means Japan in Japanese, KO means steel
  • NIHON-KO = Japan steel
  • You often see 日本鋼 (nihon ko) stamped on the backside of the blade


White Steel (SHIRO-KO or SHIRO-GAMI)

This is refined, high carbon steel. The knives made out of white steel are commonly used by sushi chefs in Japan. White steel contains more carbon compared to NIHON-KO, and its hardness and sharpness, and elasticity and ease to sharpen are all well balanced. White carbon steel knives are for experienced chefs or serious home cooks.

  • SHIRO means white in Japanese, KO means steel
  • SHIRO-KO = white steel
  • GAMI means paper
  • SHIRO-GAMI = white paper (official name of this material)
  • You often see 白鋼 (shiro ko) or 白紙 (shiro gami) stamped on the backside of the blade 


Blue Steel (AO-KO or AO-GAMI)

Blue steel, or AO-GAMI, is refined by adding tungsten and chromium to white steel. This makes the blade harder and more durable. Blue steel is mainly used in high-grade chef knives for professionals. Blue steel knives are pricey, but maintain their sharpness the longest. If you need to slice sashimi for 5 hours a day, you may want to consider switching to blue steel knives.

  • AO means blue in Japanese, KO means steel
  • AO-KO = blue steel
  • GAMI means paper
  • AO-GAMI =  "Blue Paper" (the official name of this material)
  • You often see 青鋼 (ao ko) or 青紙 (ao gami) stamped on the backside of the blade
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