Kasumi
kasumi
A two-layer construction for single-bevel knives: a hard carbon steel core forge-welded to a softer iron jacket, leaving a hazy contrast where the two meet.
Kasumi (霞, “mist”) is the standard way mid-range single-bevel knives such as the yanagiba, usuba, and traditional deba are built. A core of hard carbon steel is forge-welded to a jacket of soft iron, and when the blade is polished the boundary between the two shows as a soft, hazy line, which is where the name comes from.
The soft jacket makes the knife easier to sharpen and more forgiving than a single piece of hard steel, and it keeps the price down. It is the two-layer counterpart to san-mai on double-bevel knives, and the opposite of honyaki, where the whole blade is one piece of hardened steel. A more carefully finished version is sometimes sold as hongasumi.
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Sakai Takayuki White #2 Kurouchi Yanagi 270mm
USD 308 (checked Sep 9, 2026)
- A genuine single-bevel yanagiba forged in Sakai by blacksmith Togashi-san, hand-sharpened
- White #2 carbon takes an extremely fine edge for clean, single-draw slices of raw fish
- Kasumi construction and a soft iron jacket make it more forgiving to sharpen than a mono-steel blade