The parts of a katana are easy to list and hard to see. A glossary gives you the words. Standing in front of a real sword, the useful questions are different: where on this object does each name sit, and whose hands made that piece?
This guide answers both, from the tip of the blade to the cord tied to the scabbard. The trades come from Yasumasa Nagaoka, a sword polisher we interviewed for an Our Masters article published in August 2026, and the cord from Kiichiro Domyo, who heads the Tokyo silk-braiding house Domyo. Where a part did not come up in either interview, the description comes from a museum or a public body, and it is linked.
A katana divides first into two: the blade, and everything the blade is dressed in to be carried, which Japanese calls the koshirae, the mounting. The mounting has three zones. Between the blade and the hand sit three pieces of metal, the habaki collar, the seppa spacers and the tsuba guard. Then comes the hilt, the tsuka. Last comes the sheath, the saya, with the cord tied to it, the sageo. The Japanese Sword Museum, run by the Society for the Preservation of Japanese Art Swords (NBTHK), gives the parts of a katana mounting as a list, from the kashira at the end of the hilt to the kojiri at the end of the scabbard and the sageo. It notes that the mounting gathers the advanced skills of craftsmen from separate fields.
That list is the map. It does not say who makes each piece. Nagaoka did: "The Japanese sword is still made by a division of labour among specialists." Then he named them: "The swordsmith who forges the steel into a blade; we polishers who polish it; the craftsman who makes the scabbard, the one who makes the metal fittings, the one who makes the hilt, the one who braids the cord, the one who applies the lacquer... many people come together, and it is completed as a single composite work of art."
Count the trades in that sentence and there are seven: swordsmith, polisher, scabbard maker, maker of the metal fittings, hilt maker, cord braider and lacquerer. That is a working polisher's count, not an official register, and it is the one this guide follows.
The Metropolitan Museum of Art describes the same hand-off from the museum's side. In its essay on the technology and manufacture of the Japanese blade, once the smith has hardened the edge, the blade "is then passed on to the polisher, who will give the blade its final mirrorlike polish, and other craftsmen who will make the scabbard and sword mountings."
A blade in a plain, pale wooden scabbard is not an unfinished sword. That case is a shirasaya, a scabbard of plain wood, also called yasume-zaya, the resting scabbard. The Japanese Sword Museum explains why it exists: if a blade rusts where it touches the inside of a lacquered scabbard, a lacquered scabbard with its fittings is hard to split open and clean, so a plain case that can be opened easily was devised. It came into use in the early modern period, and it is made almost always of hō, Japanese magnolia, a wood low in oil and even in grain.
The museum's guide to handling and storing a Japanese sword puts the relationship in clothing terms: the koshirae is the outfit for going out, the shirasaya is everyday wear, and the blade is ideally kept in everyday wear. It adds that the blade should be stored where humidity is low, while the mounting should not be kept anywhere too dry. The blade and its dress want different air. When a blade rests in a pale case and its lacquered mounting lies elsewhere, nothing is missing.
A polisher does not read a blade as a list of samurai sword parts. He reads three things, and Nagaoka named them in our interview: "To put it simply: the sugata — the overall shape, the length and the curve; the hamon — the pattern that appears along the edge; and the jigane — the skin of the steel itself. You look at these three elements and take pleasure in them."
The katana blade parts below are the addresses of those three. The sugata is the whole outline, tip to tang. The hamon runs along the edge. The jigane fills the flat face; the Met's essay says the folding pattern shows in "the ji, the surface between the edge and ridgeline." The Kyoto National Museum's introductory worksheet on Japanese swords labels the same blade from the point down to the peg holes on one page. Reading a period from those features is a separate skill; what a polish does to the steel is in our guide to how a polish brings out the hamon. Here the task is to know which part you are looking at.
The kissaki is the point, "The tip area of the blade" in the Kyoto worksheet. Gifu Prefecture's glossary of sword terms calls it the fan-shaped part at the very end of the blade and names point shapes: large, small and the "boar's neck." The Bizen Osafune Sword Museum, in its page on the names of the parts of a sword, gives the judgement: the point carries the features of its period and expresses the smith's individuality well. If you look at one place first, look there.
The bōshi is the edge inside the point; Gifu's glossary defines it simply as the edge portion of the kissaki, and notes that the temper line normally turns back toward the spine there. The yokote is the line that marks off the point, and it is easiest to understand through the polisher. The Japanese Sword Museum's page on sword making and polishing describes polishing the bōshi as almost the final job of a polish: it begins by setting the yokote-suji, the yokote line, and only then is the bōshi polished, with the best finishing stone, without breaking that line. The same page describes a few lines burnished into the spine at the bōshi as, in effect, the polisher's signature. It is a signature with no name in it.
Ask what the line on a katana is called and the answer depends on which line: there are three. The hamon is the temper line along the edge, "A crystalline line along the cutting edge" in the Kyoto worksheet. The shinogi is the ridge line running between the edge and the spine; Gifu's glossary calls the band between the ridge and the spine the shinogi-ji. The hi is a groove cut along the blade; the glossary describes the long bōhi as a groove cut along the shinogi-ji to near the ridge of the point.
They come from different hands and different steps. The Met's essay explains the first: a clay mixture is applied "thicker along the spine and thinner at the edge," and after quenching, "This edge pattern is called the hamon, and is one of the most important aspects in the aesthetic appearance of a blade." The polisher then finishes the edge and the ridge differently. The Japanese Sword Museum's polishing page describes hadori, finishing the edge white along the shape of the hamon, and migaki, burnishing the spine and the shinogi-ji with a thin iron rod to a black lustre. Nagaoka gave the goal in one sentence: "At the end, you finish it to the point where the steel's surface and the temper pattern come alive."
So the white band near the edge is the hamon, the crisp ridge is the shinogi, the dark mirror above it is the burnished shinogi-ji, and the channel, if there is one, is the hi.
The ha is the cutting edge and the mune the back, "Spine of the blade" in the Kyoto worksheet. Where the blade ends and the tang begins there are two small steps, the ha-machi on the edge and the mune-machi on the back. The sori is the curve, measured, Gifu's glossary says, as the greatest distance between the back and a straight line from the tip of the point to the mune-machi. Museum records give it as a number: the Met's record for a 17th-century katana blade in a 19th-century mounting lists a blade of 83 cm with a curvature of 1.5 cm.
Nagaoka treats the curve as a product of use, not of looks alone: "There is the length, of course, but it is the matter of the sori, the curve of the blade. It is a beauty, but it is also the result of changing in response to what each era demanded — of what was easiest to use at a given time."
The nakago is the tang, the part of the blade that disappears into the hilt. Gifu's glossary adds the detail that matters here: it is the part that is not polished. It carries file marks and, usually, the smith's signature. The mekugi-ana is the hole through it, labelled in the Kyoto worksheet "For pegs attaching the hilt to the sword." The Japanese Sword Museum's page on making a sword places the tang at the end of the smith's own work: he files it, opens the peg hole and finally cuts his name. The tang is the smith's part, and the polisher leaves it alone. The hilt section shows what passes through that hole.
Where the blade meets the hilt, three pieces of metal sit in a row: the habaki collar around the base of the blade, the thin seppa spacers and the tsuba guard. Nagaoka's list gives metal fittings their own maker, "the one who makes the metal fittings."
They also show two ways of looking at a sword. The Met's essay calls the mounting's elements "all works of art in themselves" and still holds that "the blade remains the true centerpiece of the finished work." As the tsuba section shows, collectors and museums have long looked at the fittings on their own.
The NBTHK's page on mountings explains what the habaki does. It sits between the blade and the tang, and when it is seated in the mouth of the scabbard the blade floats inside, held so that it does not touch the wood. Its first job is to keep the steel off the inside of its own case.
The same page records what it was made of, and the material tells you about the owner. It was originally made in iron by the smith who forged the blade. Later copper, silver and gold were used. In the Edo period a plain copper collar was normal, while silver and gold collars went on the swords of daimyo households and on famous blades. The museum's handling guide adds that the collar is held tight in the scabbard mouth, and that pulling hard and suddenly can break the mouth; freeing only that tight section first is called koiguchi wo kiru.
The tsuba guards the hand and the seppa hold it. The museum's handling guide refits a guard in the order spacer, guard, spacer. The Fukuoka City Museum, in an exhibition of sword and spear fittings from Fukuoka samurai families, describes the spacers as the pieces that fix the guard.
In Nagaoka's account, what turned the guard into a canvas was peace. He described the Edo period, when swords were worn and not used: "metalwork, the lacquer of the scabbard, the cord of the hilt (tsuka) all turned not just black but many-coloured, and even raden, decorative inlay of iridescent shell, appeared." The Japanese Sword Museum says the same from the metalworker's side: from the middle of the Edo period guards and small fittings were made in great numbers with coloured metals and chasing, and famous makers emerged. It also notes that small fittings grouped as mitokoromono, the "three-place set," were detached from the mounting and appreciated on their own. Museums catalogue guards the same way: the Met lists a 17th-century iron guard with copper as a single entry. A case of guards with no blades is not an incomplete display.
A katana's hilt is called the tsuka. The Japanese Sword Museum describes it as the part gripped by the hand, made from the early modern period almost exclusively of hō wood, covered in white ray skin and bound with a diamond-pattern wrap. Nagaoka's list gives it its own maker, "the one who makes the hilt."
The hilt followed the people who carried the sword. According to the museum, court and ceremonial swords had no diamond wrap; wrapping in leather or cord was for warriors in the field, and around the Warring States period the ray-skin hilt bound with cord became the general custom. The grip on a katana today began as a grip for the field. Kendo practises with a stand-in: the shinai a kendo player holds.
Under the wrap is same, ray skin, which the Japanese Sword Museum notes was frequently lacquered black to withstand rain and dew. The wrap is the tsuka-ito, the hilt cord, and it was not always silk: the museum lists leather, flat braided cord, whale baleen and hemp. The Met's essay names "silk cords and wrapping, and ray-skin grips" among a mounting's elements. How a wrap is tied is a subject for a separate guide on sword cords.
The most surprising fact about the hilt is how little holds it on. Nagaoka put it this way: "A sword comes apart into pieces surprisingly easily. Though it is made on the premise of being used, it has no robustness. That it is held in place by a single bamboo peg — a mekugi — alone may be a fresh discovery for people."
The mekugi passes through the hilt and the peg hole in the tang. Take it out and the sword comes apart in a fixed order, which the Japanese Sword Museum's handling guide sets out: remove the peg, draw the blade, free the hilt by tapping the wrist of the hand holding it, then lift off the spacers and the guard, and finally the collar. In the photographs from our interview, the parts of one disassembled sword lie side by side on a table: the hilt, the small pale peg, two spacers either side of the guard, the collar, the bare blade and its scabbard. Nagaoka described what doing this with your own hands shows: "Take it apart, and you see plainly what role each part plays and what shape it has."
The fittings around the peg have names too. The Fukuoka City Museum's exhibition text lists the kashira at the far end of the hilt, the menuki, which it glosses as the fitting that hides the peg, and the fuchi at the guard end.
A katana's sheath is called the saya, and it takes two of the seven trades on Nagaoka's list, "the craftsman who makes the scabbard" and "the one who applies the lacquer." The Japanese Sword Museum's page on mountings records that early-modern katana and short swords had lacquered scabbards as a rule, with black roiro lacquer for the formal pair, and that from the middle of the Edo period scabbard lacquer looked for variety too, with finishes set with fine shell or made with eggshell among them.
The Fukuoka City Museum's text names the sheath's fittings in one passage: the koiguchi, the mouth that holds the blade in the scabbard; the kojiri at the scabbard's tip; and the kurikata, through which a cord is passed.
The scabbard is where a polisher's work can be undone in a moment. Nagaoka was blunt: "even a sword polished with the greatest care will be scratched the moment the customer takes it home and draws it roughly from the scabbard (saya)." The museum's handling guide gives the other half: rust on a blade often comes from the blade touching the inside of the scabbard, which is a fault of the scabbard, to be fixed by consulting a scabbard maker; rust on the blade itself goes to a polisher. Two of the seven trades look after the same blade from two sides.
The sageo is the cord passed through the kurikata and tied to the scabbard, and its maker is a braider, not a metalworker. Kiichiro Domyo told us: "The cord that samurai wound on their swords, called sageo, had always been made as Kumihimo, and thread merchants like us supplied a great many craft braids." When the ban on wearing swords came, he explained, the braiding once used for sageo was turned to the obi-jime, the cord that holds a kimono sash; the story is in our history of the silk-braiding craft behind the sageo.
The parts of a katana do not age together. The Met's katana shows it in its date line: "blade, 17th century; mounting, 19th century." The record describes the mounting as silver decorated in various metals with waves, fish and aquatic plants, by Iwamoto Kansai, a student of the eighth and last master of the Edo-based Iwamoto School of fittings makers. Three kinds of change shaped this: the trades divided, the use of the sword changed, and the law intervened.
The division of trades is old, and it left names behind unevenly. The Japanese Sword Museum's polishing page notes that specialist polishers are already attested in the time of the retired emperor Toba, in the 12th century. Its page on mountings says that the appraisal of small fittings began with the works of the Gotō family, founded by Gotō Yūjō, who served the shogun Ashikaga Yoshimasa, while blades were appraised by the Hon'ami family.
Who paid shaped the work too. The Fukuoka City Museum's text says that daimyo and senior samurai owned lavishly made mountings, while ordinary samurai put gold and silver work on only some of their fittings. For the households at the top, see our guide to the daimyo households whose swords carried silver and gold collars.
The polisher's own name does not survive. Nagaoka said it without complaint: "The name of the person who made the blade survives for centuries." A moment later: "So then, who polished it? That, no one will ever know."
Use changed the fittings first: in the Edo peace, as Nagaoka described above, metalwork, lacquer and cord turned decorative. Then the law changed what could be worn. On 28 March 1876, according to the National Archives of Japan's record of the sword-wearing ban, the Council of State prohibited the wearing of swords, except with full court dress and for soldiers, police and officials in uniform. The blades stayed; the cords lost their purpose and, as Domyo described, their braiding went into the obi-jime.
The 20th century remounted the sword again. Nagaoka noted what happened when there was demand for military swords, guntō: "when demand for guntō arose, old swords were revived with only their fittings remade." An old blade, a new mounting, a new purpose. In each change the blade stayed while its dress changed. That is worth remembering when a label gives a sword two dates.
There are three distances from which to see the parts of a katana, and each brings you closer.
The first is open to anyone: a museum case, such as those at the Japanese Sword Museum in Ryōgoku; our guide to where Tokyo's real swords and armor are on show sorts the options. From there you can read the point, the temper line and the ridge. You cannot see the peg or how the hilt is held, and Nagaoka is frank about the difference a companion makes: "With someone beside you, understanding deepens, and a familiarity grows."
The second is open to those who know where to look. Our interview article notes that the NBTHK holds a modern sword-craft exhibition, the Gendai Tōshoku-ten, once a year: one of the few public stages where these craftsmen's work is shown, in the form of a competition.
The third needs someone to put a sword in your hands: holding it and taking it apart. Nagaoka described how he begins: "First, I have them hold the real thing in both hands. Not in the sense of drawing it from the scabbard — first, just take it in hand." Then they draw the blade and look at it; after that the parts come off one by one, and what changes is the reason this guide exists: "Take it apart and put it back, and you come to feel differently about what you had only been gazing at until then."
Two of the seven trades speak in this guide, and both describe a present that is thin and still moving. Polishers, by Nagaoka's own sense of it, number "a hundred at most" across the whole country, and the work is not lacking: "If you ask me for a new polishing now, the lead time is a three-year wait." What he wants to change is how closed the trade has been. As our interview records, he holds introductory courses where beginners can hold a real sword, and takes groups to the nearby sword museum with someone knowledgeable beside them. "Now it is the reverse," he said, "please, just take an interest; whatever you don't understand, ask us."
The braiders face a different pressure. From the Meiji era onward, as Western braiding machines arrived and many companies mechanized, Domyo's house went the other way; in the time of its sixth-generation head, Domyo told us, "the policy was set to use no machines at all and to make Kumihimo by handwork alone." Now the thread itself is scarce: "Domestic silk thread has now become so hard to obtain that it makes up only about 0.05% of the total used, but we use both domestic and foreign thread, and with domestic thread alone our company uses about 2% of Japan's entire production volume."
Pick up a mounted katana and you meet its parts in this order. The saya, with the sageo through the kurikata and the kojiri at its tip. The koiguchi, where the habaki holds the blade off the wood. The blade itself: the mune and the edge, the sori between them, the hamon, the shinogi ridge, a groove if there is one, the yokote, the bōshi and the kissaki. Then the hilt, if someone shows you how: the mekugi out, the tsuka off, the seppa and tsuba lifted, the nakago bare with its peg hole.
Behind each of those names there is a trade. By one polisher's count there are seven.