Signed vs. Unsigned Japanese Swords: Value and Appraisal

The mei is a sword's "identity certificate"

The mei (signature) engraved on the nakago (tang) of a Japanese sword is the maker's signature. Engraved in formats such as "○○koku juu △△saku" or "Tenka ichi △△," the mei carries meaning beyond mere identification. It is a declaration that the swordsmith bears responsibility for their work, and proof of the sword's origin.

In contrast, swords without a mei—mumeizashi (unsigned blades)—are quite numerous among surviving Japanese swords. The reasons vary. Sometimes the mei is lost when the nakago is shortened through suriage (re-shaping). Sometimes the mei was intentionally left uncut. Other times, the mei has become illegible due to rust or damage.

Loss of mei through suriage—from ōdachi to uchigatana

The most common cause of unsigned swords is "suriage" (re-shaping of the blade). Ōdachi and tachi, which flourished during the Nanboku-chō period, were often shortened during the Edo period and later to become more portable uchigatana or wakizashi. When the nakago was cut down in this process, any mei engraved on it was lost.

Many famous blades from the Nanboku-chō period are large works that became unsigned through later suriage. Excellent koto from the Kamakura period also lost their mei through practical modifications during the Sengoku through Edo periods.

Great blades without signatures—the world of "meibotsu mumeizashi"

Being unsigned does not necessarily mean lower value. The term "meibotsu mumeizashi" (famous unsigned blades) exists precisely because historically renowned swords include many unsigned examples.

The "Dōji Kiri Yasutuna," counted among the Tenka Go Kens (Five Swords Under Heaven), is a National Treasure tachi currently housed in the Tokyo National Museum. Its long nakago bears only the two characters "Yasutuna" as its mei, with specific details of manufacture date and origin determined through swordsmith tradition and expert appraisal. Many famous blades like "Onimaru Kunitsuna," which lost their mei to suriage yet had their makers identified through tradition and distinctive hamon characteristics, exist throughout history.

In NBTHK (Nihon Bijutsu Token Hozon Kyokai) examinations, unsigned blades are classified and evaluated as "maker unknown," "○○ tradition," or "○○ style," with estimated makers and periods based on hamon, jihada, and shape characteristics recorded in the appraisal certificate.

The signed or unsigned blade and market price

In the sword market, the presence or absence of a mei has significant influence on pricing. Generally, blades of the same quality and period with individual signatures command higher prices than unsigned examples. This is because the mei identifies the maker, and that swordsmith's reputation and renown are reflected in the price.

However, even with signatures of famous swordsmiths, the possibility of a gimei (false signature) complicates appraisal. False signatures bearing the names of historical masters—Masamune, Yoshihiro, Gō no Yoshihiro—were produced in great numbers from the Edo period onward, and gimei determination is part of NBTHK's important sword appraisal process. When gimei is confirmed, a blade may be reclassified as unsigned.

Conversely, an unsigned blade identified through jihada, hamon, and shape as the work of a renowned swordsmith may command a higher price than a Masamune with a false signature. The paradox "Masamune unsigned is more trustworthy than Masamune with false signature" is often spoken of in sword circles.

Reading mei in practice—the pleasure of signed blade appreciation

Signed blades deepen appreciation through decoding the signature text. Characters used in mei such as "kuni" (province), "juu" (resident), "saku" (made), and "motte" (by) follow set patterns, but each swordsmith's script style and individual character forms reveal personality.

The technique of carving mei is itself an art. The way characters are engraved using a chisel—their depth, width, and chisel type—can reveal the swordsmith's skill level. Comparing multiple works by the same maker allows estimation of production period (early, middle, or late period) through changes in signature script style.

Summary—mei is the entrance, the essence is the blade itself

Whether a blade is signed or unsigned is an important element in sword evaluation, but it is merely the entrance to assessment. The ultimate value of a sword is determined by the quality of the blade itself—the beauty of the jihada, the scenery of the hamon, and the balance of sori and sugata. The mei provides a path to understanding the maker, but relying too heavily on the signature misses the point. Cultivating the eye to appreciate the blade directly is the true essence of Japanese sword appreciation.

Distinguishing authentic from false mei—perspectives for detecting gimei

In Japanese sword appraisal, determining the authenticity of mei signatures is an important challenge. Because swords bearing signatures of master craftsmen command high prices, gimei blades—those with false signatures added later—have been created in large numbers since the Edo period.

Several perspectives exist for detecting false signatures.

• Whether the rust color of the mei matches the rust color of the entire nakago. Mei engraved after the fact often show rust coloration different from the nakago's patina.
• Whether the carving depth and cross-sectional form of the cut marks align with the engraving techniques of the period's swordsmiths.
• Whether the script style, character forms, and signature composition are consistent with known examples.

NBTHK examiners and appraisers from families like Honami make authenticity judgments based on extensive experience viewing actual blades. With advances in digital technology, methods using X-rays and 3D surface analysis to verify the age of carving marks are now being adopted.

While the presence of a mei is part of a blade's appeal, the truest path to deepening Japanese sword appreciation is to maintain the stance of appreciating the blade itself—its beauty and craftsmanship—rather than relying excessively on signatures of uncertain authenticity.