Japanese Knife Finishes: Kurouchi, Kasumi, Nashiji, Tsuchime, Migaki and Damascus Explained

The short version

A Japanese knife finish is the state the blade surface is left in after forging and grinding. Six names come up again and again on Japanese knife listings:

• Kurouchi (黒打ち): the black forge scale left on the upper blade^[1][3].
• Nashiji (梨地): a matte, pebbled pear-skin texture; sources disagree on how it is made^[2][6].
• Tsuchime (槌目): dimples hammered into the blade face^[1][7].
• Migaki (磨き): polished, from a satin sheen to near-mirror; a full mirror polish (鏡面, kyōmen) is the far end^[1][8][9].
• Kasumi (霞): the misty look of a polished clad blade, and also the name of the clad construction itself, as opposed to single-steel honyaki^[10][11].
• Damascus / suminagashi (墨流し): many layers of steel welded into the cladding, with the layers showing as a pattern^[14].

The knife retailer Cutlery and More puts the point plainly in its kurouchi guide: the grind, the steel hardness and the edge geometry are what matter most in how a knife performs^[3]. Choose a finish for its looks, its care and how you want it to age. Do not choose it for cutting performance: the food-release claims made for textured finishes come without measurements (see below).

A finish is not a construction

The finish is the outer surface; the construction is what the blade is made of. Most Japanese blades are either one steel all the way through (mono-steel, of which differentially hardened honyaki is the traditional form) or a hard cutting steel forge-welded to softer cladding (kasumi, san-mai and their variants)^[11][15]. The two are linked, because finishes are often influenced by how a knife is constructed^[1], and many Japanese blades carry several finishes at once: kurouchi or nashiji on the upper blade, a hazy kasumi band on the cladding mid-blade, and the bright core steel at the edge^[1].

Japanese shops sort knives the same way. The Japanese-language store of the knife shop Musashi files knives by finish under ダマスカス (Damascus), 霞 (kasumi), 黒打 (kurouchi), 槌目 (tsuchime) and 梨地 (nashiji), and lists 本焼き (honyaki) as a separate category^[9]. For the construction side, read our guides to what honyaki is, hocho vs honyaki and Damascus vs mono-steel.

Kurouchi (黒打ち): the blacksmith finish

Kurouchi is the black oxide scale that forms on the blade in the forge, left on the flats instead of being ground and polished off. Retailers translate the word as "black forged" or "blacksmith's finish"^[1][3]. Only the bevel is ground, which gives the familiar black upper blade above a bright band that runs down to the edge^[4][1].

How it is made. Natural kurouchi exists only on a forged knife, and its texture, colour and durability vary by maker and steel^[3]. Cutlery and More separates three versions: the natural forge scale; natural scale sealed with a food-safe lacquer, which slows patina and wear; and an artificial kurouchi applied in production with black oxide or acid baths, which it notes can appear even on stamped knives^[3]. Knifewear, a Canadian Japanese-knife retailer, adds that some makers deepen the black with dye^[2].

What it changes in practice. The blog of the online knife shop Hocho Knife says the scale works as a coating that reduces reactivity on carbon steel^[5]. Knives and Stones, an Australian retailer, is more careful: kurouchi gives the steel it covers some protection from rust, but the bare bevel and edge still need care^[4]. Knifewear notes both sides: the layer can act as a moisture barrier that slows rust, yet its rough surface gives moisture more to cling to, so the knife has to be dried carefully even when the steel is stainless^[2]. On food release the claims are weak. Knifewear says kurouchi "may sometimes" let food stick less, while Cutlery and More calls the finish primarily visual and warns that a kurouchi line set low on the blade can add drag on dense, wet food such as sweet potato and apple at first^[2][3].

How it ages. Kurouchi is a living finish. It wears off slowly where the knife is handled and used most, and over the years it can wear off in spots^[2][4]. In the first few uses it may transfer slightly to your fingers; Cutlery and More says that is not a defect^[3]. Hand wash, dry at once, oil with camellia or mineral oil between uses, and never scrub with abrasive pads, which take the black layer off^[4]. Our rust care guide covers the routine.

Where you see it. Kurouchi is typical of hand-forged Japanese knives, most often rustic carbon-steel gyuto, santoku, nakiri and bunka^[1][4]; for the steels underneath, see Aogami vs Shirogami. Price: leaving the scale on saves the time of grinding and polishing it off, which saves production cost, but Cutlery and More adds that price does not always follow the finish^[3].

Nashiji (梨地): pear-skin texture

Nashiji is a matte, finely pebbled texture named after the skin of the Asian nashi pear. It looks subtly stippled and semi-matte, and is usually on the upper part of the blade^[1][6].

How it is made: the sources disagree. Knifewear and Cutlery and More describe nashiji as a kurouchi blade polished down until the black scale is removed but some texture is left^[2][1]. Knives and Stones says the texture is made in more than one way, forging and sandblasting among them, with the high spots then lightly polished^[6]. A nashiji label therefore tells you the look, not the method.

What it changes in practice. Nashiji hides small scratches better than a polished blade^[6]. Knifewear credits it with a little more grip and food release than a smooth blade, "but less noticeably" than a hammered finish; Knives and Stones says it may help food release but does not guarantee that food will not stick^[2][6]. The downside is moisture: the texture gives water more surface to settle in, which Knifewear says raises the rust risk when knives are left to air-dry, even on stainless steel^[2].

How it ages. On carbon-clad blades the texture can darken a little over time. Wash nashiji by hand, use a soft brush for the pits and dry it at once^[6]. Where you see it: on clad Japanese knives with stainless or carbon cladding, typically gyuto, santoku and bunka^[6][1]. None of the sources we read gives a price effect for nashiji.

Tsuchime (槌目): hammered dimples

Tsuchime is a field of shallow dimples hammered into the blade face above the bevel. The word means "hammered"^[1][7].

How it is made. The blade face is struck repeatedly with a hammer; makers use round, square or diamond-shaped hammers, and some smiths make their own for a particular pattern^[1][2].

What it changes in practice. In the sources we read, tsuchime gets the strongest food-release claims. Knifewear says it is "great with food release" because air is trapped between blade and food, and Cutlery and More says the hammer marks aid food release; Knives and Stones says the dimples may help, but do not guarantee that slices will not cling^[2][1][7]. Knifewear also mentions more traction for a pinch grip, and a cost: moisture settles in the hammer marks, and the cladding can rust if the knife is not wiped^[2].

How it ages. The texture is in the steel and does not wear off in normal use; on carbon steel the dimples darken over time. Brush the dimples under running water and dry at once^[7]. Where you see it: on san-mai Japanese knives, gyuto, santoku, nakiri and bunka among them, in both stainless and carbon steel^[1][7]. None of the sources we read gives a price effect for tsuchime.

Migaki (磨き) and mirror polish

Migaki means "polished" and covers any polished blade, from a soft satin sheen to near-mirror; a full mirror polish, labelled 鏡面 (kyōmen) in Japanese listings, is the far end.^[1][8][9]

How it is made. The blade is polished with progressively finer abrasives, and where the polishing stops sets the look^[8]. A machine-made migaki can look very different from the slower polish of a small maker, and the result ranges from cloudy and matte to almost mirrored^[2]. A mirror polish goes through more grits and buffing; Knifewear calls it the most labour-intensive finish^[2].

What it changes in practice. A polished surface shows fingerprints and water spots, so wipe it after use, and avoid abrasive scouring pads, which scratch it^[8]. A mirror polish demands gentle handling throughout, and restoring a scratched one takes a lot of work^[2]. Knifewear makes two claims that pull in different directions: the slick surface gives less pull when slicing, which suits sujihiki, yanagiba and 240–270 mm gyuto, yet food, starchy vegetables especially, tends to stick more to a highly polished surface than to nashiji, tsuchime or kurouchi^[2].

How it ages. On a polished carbon-steel blade the patina develops more slowly and more visibly^[1], and on a polished blade scratches are more noticeable than on a textured one^[2]. Where you see it: migaki is the usual finish on stainless and stainless-clad knives, and on most German forged knives^[8][1]. Knifewear recommends a mirror polish for slicers, and its mirror-polished examples are both honyaki; Musashi lists a mirror-polished white-steel honyaki kiritsuke (白本焼 鏡面)^[2][9]. Price: Knifewear says the price of a mirror polish typically reflects the work, and that most mirror-polished knives it sells carry a hefty price^[2].

Kasumi (霞): a look and a construction

Kasumi, "mist" or "haze", names two things: the misty look of a polished clad blade, and the clad construction itself, hard steel forge-welded to soft iron, which is the everyday alternative to single-steel honyaki.^[10][11][12] Which one a listing means depends on the word next to it: "kasumi finish" is the look, "kasumi knife" usually means the construction.

Kasumi as a finish. After grinding, the blade is finished on progressively finer stones; the hard core steel comes up bright while the softer cladding stays hazy, and that contrast is the kasumi look^[10]. Cutlery and More describes it as a cloudy, semi-polished band on the cladding mid-blade^[1], and Japanese shops file 霞 as a finish next to 黒打, 槌目 and 梨地^[9].

Kasumi as a construction. The Hocho Knife blog describes honyaki and kasumi as the two basic categories of Japanese wa-bocho: honyaki is forged from high-carbon steel alone, while kasumi joins a piece of soft iron (jigane) with a piece of high-carbon steel, and takes its name from the hazy look of the soft iron^[11]. The knife shop Kireaji gives the same definition, soft iron jigane plus hard steel hagane, usually forge-welded in the awase method, with the name coming from the cloudy boundary that appears after polishing^[12]. Hon-kasumi knives are built the same way, often with higher-quality steel and more work^[11]. This is the sense our honyaki vs kasumi guide uses, and the "kasumi line" in our hocho vs honyaki guide is the same boundary.

What it changes in practice. Kasumi is most often seen with a carbon-steel core in softer iron cladding, and Knives and Stones says to treat such a knife as carbon steel: the soft iron cladding patinas and rusts, so hand wash, dry at once and oil it if it is going away for a while^[10]. That differs from a stainless-clad carbon knife, which rusts only at the exposed edge^[15]. Knives and Stones also lists kasumi-finished knives with stainless cores such as SG2 and Ginsan^[10], so check the cladding before you assume the care. The usual carbon cores are compared in Aogami vs Shirogami.

How it ages. The soft iron cladding patinas with use^[10]. Over many years and sharpenings the kasumi line also shifts as the bevel is reground; Knives and Stones calls that normal and says a polisher can bring it back^[10]. Where you see it: on single-bevel knives such as yanagiba, usuba and deba, and on many clad double-bevel blades^[10]. Price: kasumi knives cost less than honyaki^[11]; our honyaki guide gives broad price ranges for both.

Not to be confused with the brand. Kasumi is also a knife brand. The Canadian retailer Chef Supplies says Kasumi knives are made by Sumikama Cutlery in Seki, and describes its Kasumi Damascus series as a VG-10 core inside layers of stainless steel^[13]: a stainless Damascus knife, not the iron-clad construction described here.

Damascus and suminagashi (墨流し)

Damascus, often called suminagashi in Japan, is cladding made of many layers of steel welded together, with the layers showing as a wavy or swirling pattern. Knifewear notes that purists would call it "pattern-welded" steel, and that suminagashi is named after a dyeing technique in which ink is swirled on water and taken up by paper or cloth^[14][2].

How it is made. On most Japanese Damascus knives the layered steel is the cladding, not the core^[14]. Many blacksmiths buy steel that has been layered by the steel maker, while some fold and weld the layers themselves^[14][2]. The pattern is then brought out in different ways: an acid etch turns the steel dark grey while nickel layers stay silvery, and other blades are mirror-polished or left with a kurouchi finish^[14][2]. Coreless Damascus, with the same layered steel through the whole blade, also exists^[1]. How to tell forged layers from a pattern printed on the surface is in our guide to spotting fake Japanese knives.

What it changes in practice. Knifewear's own summary is that the core steel does the heavy lifting and the Damascus cladding is there to make the knife pretty and more durable^[2]. Care depends entirely on what the layers are. Tojiro's CLASSIC Damascus gyuto (F-655) has a VG10 core in layered stainless-steel cladding^[18]. Hatsukokoro's Kumokage sujihiki, by contrast, has an Aogami #2 core in soft-iron Damascus under a kurouchi finish; Cutlery and More calls the cladding reactive and warns that the knife will rust if it is not cleaned and dried promptly, and will build a protective patina if it is^[16].

Where you see it: on Japanese knives both hand-forged and stamped^[1]; our Damascus knife guide covers the knives themselves. Price: Damascus usually means more work for the steel maker and the blacksmith, and Knifewear says it is not known for being easy on the wallet^[2]. One like-for-like example is in the price section.

All finishes compared

Each cell below comes from the sources linked in the sections above. "Reactive" means whether the surface itself patinas or rusts; the edge of a carbon-steel knife is reactive under any finish.

Food release: what the claims rest on

Every food-release claim we found for Japanese knife finishes comes from a retailer, and none of them cites a measurement. We also did not find a controlled test. The claims differ mainly in how strongly they are worded:

Read these as shop experience, not findings. Cutlery and More's own conclusion is that the grind, the hardness and the edge geometry matter most in how a knife cuts^[3], and a surface texture does not change any of those. If food release matters to you, look at the grind and the blade geometry before you look at the finish.

How the finish affects price

Where the sources mention price at all, they tie it to labour: a finish that saves work costs less to make, and one that adds work costs more. What they say, finish by finish:

• Kurouchi: less work, because the scale does not have to be ground and polished off, which saves production cost; but price does not always follow the finish^[3].
• Mirror polish: the most labour-intensive finish, with a price that typically reflects it^[2].
• Damascus: more work for the steel maker and the blacksmith, and not known for being cheap^[2].
• Kasumi construction: less expensive than honyaki^[11].
• Nashiji, tsuchime, migaki: the sources we read give no consistent price direction. Compare within one maker's range instead.

A like-for-like example from one maker: on Tojiro's own Japanese web store, the CLASSIC gyuto 210 mm (F-808) is ¥14,300 and the CLASSIC Damascus gyuto 210 mm (F-655) is ¥24,200, tax included, both checked on 27 October 2026^[17][18]. Both have a VG10 core, a 210 mm blade and a laminated-material handle; the F-808 is clad in 13-chrome stainless, the F-655 in layered stainless steel^[17][18]. The cutting steel is the same; the visible difference is the Damascus cladding, and it comes with a ¥9,900 higher price.