Choosing Koshirae — Finding the Right Mounting for Your Blade

Koshirae: The Deep Meaning Held by Sword Mountings

Koshirae (sword mountings) is the collective term for the outer fittings that adorn a sword. Composed of the handle, tsuba, scabbard, and various metal fittings working in unity, koshirae both brings out the beauty of the blade while eloquently telling the story of the era and culture in which the sword lived. However excellent a blade may be, without appropriate koshirae, it cannot fully express its true beauty and value.

Koshirae is not merely decoration—it is a cultural medium of expression that reflects the historical background, function, and the owner's status and aesthetic sensibility as one unified whole. The mountings commissioned by daimyo during the Edo period were themselves proof of the daimyo's education and wealth. The patterns of the tsuba, the wrapping of the handle, the color and patterns of the scabbard lacquer—all were designed under a unified aesthetic and formed a world of beauty inseparable from the blade itself.

When actually acquiring a sword, it is essential to evaluate the quality of the blade and the quality of the koshirae from separate perspectives. The certificate of authentication that comes with the blade certifies the value of the blade itself; the age and quality of the koshirae must be judged separately. Whether the koshirae has been transmitted together with the blade as something of historical provenance, or whether it was remounted at a later time, changes the weight of the story that their combination tells. When purchasing or receiving a sword, it is recommended that you receive careful explanation regarding both the blade and the koshirae, and make your judgment after understanding the relationship between the two.

Shirasaya and Koshirae: Division of Purpose—A Dual Structure for Storage and Appreciation

An important concept that collectors must first understand is the division of roles between shirasaya and koshirae. Shirasaya is a plain, unadorned wooden scabbard made of magnolia wood intended solely for the protection of the blade. It has no decorative elements whatsoever, and serves as a pure storage container designed to protect the blade from moisture, impact, and oxidation. The interior is finished with precision to match the shape of the blade, and is designed so that the blade does not shift within and become damaged.

Koshirae, by contrast, is decorative outer fittings for viewing and display. The ideal practice of sword collection management is to keep the blade in the shirasaya during storage and replace it with the koshirae when viewing or displaying. When a single sword has both a shirasaya and koshirae, the completeness of the collection is greatly enhanced.

If a blade remains in its koshirae during extended storage, slight moisture and dirt tend to accumulate inside the scabbard, creating an environment unfavorable for the blade. The basic practice for keeping a blade healthy over the long term is to develop the habit of returning the blade to its shirasaya after viewing or displaying it to guests, once you have checked its condition. Conversely, even if you acquire a sword that remains in its shirasaya, it is worth considering whether an appropriate koshirae separately exists for that sword, or whether one should be commissioned in the future. Understanding the dual structure of shirasaya and koshirae is an indispensable perspective for managing a collection over the long term.

Uchigatana Koshirae—The Standard Form of Edo Warrior Culture

Uchigatana koshirae is the mounting style most commonly used for uchigatana swords produced after the Edo period. Designed for wearing the sword at the waist, functional metal fittings such as the kurikata, kaeshi-zuno, and ishizuki are positioned at various points.

The beauty of uchigatana koshirae lies in the perfect harmony of practicality and decoration. The lacquered scabbard, the handle wrapped with sharkskin and silk thread, and a diverse array of materials including iron, brass, and metalwork combine to determine the formality of the entire koshirae. When selecting uchigatana koshirae, it is important to carefully examine whether the design of the koshirae as a whole is in accord with the manufacturing era of the blade, its rank, and the impression of its hamon.

When actually handling uchigatana koshirae, it is also important to confirm that the blade fits snugly in the scabbard without excessive tightness or gaps, and that the handle is firmly fixed to the blade. The interior of the handle is structured so that the blade is fixed to the handle by means of mekugi. Whether the mekugi is maintained in proper condition is one clue for determining the completeness of the koshirae. The tsuba, kozuka, menuki, and other metal fittings each possess designs that reflect their era, and by paying attention to how these fittings work together, one can develop a deeper understanding of the background of the koshirae as a whole.

Tachi Koshirae—The Classical Form of the Kamakura and Muromachi Periods

Tachi koshirae is the mounting style for tachi swords produced from the late Heian through Muromachi periods. Since tachi swords are worn with the blade facing downward, suspended from the waist, a special suspension fitting called "ashiganamono" is attached to the lower part of the scabbard. This suspension fitting is the most clear visual distinction from uchigatana koshirae.

Tachi koshirae is rarely used in practical application in the modern age, but it is essential knowledge for correctly evaluating old tachi swords and demonstrating their historical authenticity. When an old tachi comes with tachi koshirae, its documentary and cultural value is greatly enhanced.

When appreciating tachi koshirae, by observing not only the position and design of the ashiganamono but also the curve of the entire scabbard and the patina of the fittings, one can sense the weight of time that the tachi has experienced. Tachi koshirae exists in far fewer numbers than uchigatana koshirae, and examples in good condition become valuable documentary materials in themselves. When tachi and their koshirae have been transmitted as a complete set, it is appropriate to regard both together as one completed cultural property, rather than evaluating them separately.

Hantachi Koshirae—A Beautiful Compromise of the Transitional Period

Hantachi koshirae is an eclectic form that possesses the hanging mechanism of tachi koshirae while also allowing for a method of carrying closer to uchigatana koshirae. It emerged during the transitional period from the late Muromachi through Azuchi-Momoyama periods, and represents a product of the age that reconciled the formality of tachi with the practicality of convenient sword-wearing.

This style embodies the transitional nature of the era and possesses unique historical and cultural value; among collectors it is particularly highly regarded.

When examining hantachi koshirae, observing how the remnants of the suspension fittings characteristic of tachi and the practical fitting configuration closer to uchigatana coexist within a single mounting reveals the ingenuity unique to that era. In the respect that it embodies the spirit of the age when the style of sword-wearing changed from tachi to uchigatana, hantachi koshirae offers fascinating insights for understanding the history of swords.

Selecting Koshirae Suited to Era and Formality Protects a Sword's Value

The most important aspect of selecting koshirae is ensuring harmony with the era, rank, and origin of the sword. Combining a Kamakura-period tachi with an Edo-period uchigatana koshirae would be historically and culturally inappropriate and would greatly diminish the sword's value. When commissioning a new koshirae, selecting designs and materials appropriate to the era of the blade becomes a responsibility to preserve the sword's historical authenticity.

When selecting or remounting koshirae, checking the following points will make judgment easier:

• The era and origin of the blade and the assumed style of koshirae (uchigatana, tachi, or hantachi) do not contradict each other
• The designs of the fittings and scabbard lacquer that accompany the koshirae harmonize with the rank of the blade and the impression of its hamon
• The koshirae itself has old provenance or transmission history, or will it be newly commissioned
• The overall preservation state of the koshirae (scabbard cracks, lacquer flaking, damage to the handle wrapping, etc.)

By confirming each of these points one by one and consulting with experts, the information necessary to select koshirae worthy of the blade is assembled.

When in doubt, consulting with a trusted expert is strongly recommended. An experienced sword specialist should be able to make a comprehensive judgment of the era, swordsmith, and historical context of the blade and koshirae, and propose the optimal choice.

The Materials and Craftsmanship of Koshirae—The Names of Each Part that Create Beauty

Each part that makes up the koshirae involves a specialist craftsman. The scabbard (saya) receives lacquer work by a nurishi (lacquer artisan), while the handle (tsuka) is wrapped with sharkskin and silk thread or leather cord by a tsukamakishi (handle-wrapping artisan). The tsuba is crafted by a tsuba artisan, and menuki, kozuka, and kougai by sculptural metalworkers. Only through the convergence of the skills of many specialist craftsmen is a single koshirae completed.

When commissioning a new koshirae, detailed consultation with these craftsmen is indispensable. The choice of materials, patterns, and colors must be made in harmony with the era and formality of the blade while reflecting the aesthetic sensibility of the owner. The creation of koshirae typically requires several months to over a year, and it is only when the completed koshirae and blade become one that the sword's beauty is fully expressed.

To keep koshirae beautiful over a long period, care must be taken in daily handling. Handle wrapping and sharkskin are vulnerable to moisture and direct sunlight, which cause fading and deterioration. Depending on their material, the tsuba and other metal fittings may oxidize or discolor, so maintenance should consist of gently wiping with a soft, dry cloth, and strong rubbing or the use of polishing compounds should be avoided. The lacquer on the scabbard is similarly vulnerable to impact and sudden temperature changes, so attention must be paid to the storage environment.

If there is concern about the condition of the koshirae, or if damage or looseness is discovered, do not attempt disassembly or repair on your own; always consult a specialist craftsman. Because koshirae consists of many parts assembled together, mishandling even one part can compromise the balance of the whole. Consulting with experts is the surest method of protecting the value of the koshirae and its blade.