January, 2016



Meito Kansho

Examination of Important Swords


Juyo Bunkazai

Important Art Object


Type: Tachi

Mei: Tsugutada

Owner: Mori Memorial Shusui Museum


Length: 2 shaku 6 sun 2 rin (78.85 cm)

Sori: 8 bu 8 rin (2.67 cm)

Motohaba: 9 bu 9 rin (3.0 cm)

Sakihaba: 6 bu 4 rin (1.95 cm)

Motokasane: 2 bu 3 rin (0.7 cm)

Sakikasane: 1 bu 3 rin (0.4 cm)

Kissaki length 1 sun 7 rin (3.25 cm)

Nakago length: 7 sun 1 bu 3 rin (21.6 cm)

Nakago sori: slightly less than 1 bu (0.3 cm)




This is a shinogi zukuri tachi with an ihorimune. It is a little wide, and the widths at the moto and saki are different. There is a large hiraniku, a large koshizori, funbari and a chu-kissaki. The jihada is itame mixed with mokume, the entire jihada is well forged, and there are jifu (dark areas in the steel) and sumi hada (dark and clear hada areas). The fine visible jihada is a chirimen-hada (it has a crepe-like appearance). There are thick dense nie, chikei and pale jifu utsuri. The hamon is mainly ko-midare mixed with ko-choji, ko-gunome and some places have hotsure. There are hotsure, ko-ashi, a dense nioiguchi, and the inside of the hamon has abundant dense nie. Around the center, the nie become rougher, there are fine kinsuji and sunagashi, and the top of the hamon is mixed with yubashiri, small tobiyaki, abd uchionoke. The hamon is yakiotoshi at the koshimoto.

The boshi is straight with a komaru, a small return, and nie suji. The nakago is ubu, the tip is a shallow kurijiri, which becomes a kengyo style, and the yasurime are a o-sujichigai. There is a one mekugi-ana, and on the omote under the mekugi-ana, there is a distinctive large size two kanji signature made with a thick chisel.

According to the gEngishikih, a record which listed laws and regulations and which was published in the early half of the Heian period, Bitchu no kuni (Bitchu Province) contributed iron and hoes (for farming work) and salt to the imperial court. From this, it appears that that province was famous for iron production since early historical times, the same as for the other Chugoku areas. The province to the east of Bitchu is Bizen, and on the north, the neighboring province is Hoki, and all of these areas are supposed to have had optimal conditions for sword production. From the number of signed swords we have today, we can imagine that there was a large number of smithsworking in this area.

Notably, the Ko-Aoe school is well known along with the Yamashiro and Yamato schools, and was famous for sword production along with Ko-Bizen, Ko-Hoki and Ko-Kyushu. The Gotoba-infs (emperor) Ban-kaji smiths such as Sadatsugu, Tsunetsugu and Ietsugu are well known, and their last work was supposed to have been done around the mid-Kamakura period. The Ko-Aoe tachi are narrow and elegant with delicate shapes, and this reflects this period. Their hamon are similar to the neighboring Ko-Bizen work, and there are frequent nie, but usually the nioiguchi is worn down, and people consider this to be part of their quiet elegant character.

In the historical sword book gMeikanh, Ko-Aoe Tsugutadafs work is listed around the Joei period (1232-33), and he is supposed to be either Ietsugufs or Yasutsugufs son or grandson. He has only six signed works existing: this tachi, a Tokyo National Museum tachi (from the Tanzen shrine), a Tokubetsu Juyo Token classified blade, and three Juyo Token classified blades. His signed with large kanji in the center of the nakago, and either under or over the mekugi-ana in two ways or styles. The other Ko-Aoe smiths were more likely to sign under the mekugi-ana. All his hamon are low, mainly ko-midare mixed with ko-gunome, and have small vertical variations. There are ko-nie, some kinsuji, sunagashi, and a worn down nioiguchi, which is a characteristic classical style.   

This sword has a perfect ubu nakago, and some of the original yasurime clearly remain. Ko-Aoefs characteristic strongly carved signature style is still seen with strong chisel marks. Also, the upper half of the sword is a little wide and has a large hiraniku. There is a healthy shape and this is a heavy tachi. It is in an amazingly good state of preservation. Besides the long tachi shape, the jihada is refined from the moto to the saki, and is an itame mixed with mokume. The entire jihada is well forged, and there are jifu and sumi hada. The fine visible jihada shows a prominent chirimen-hada, which is a characteristic Ko-Aoe jihada. The hamon is natural appearing and very classic looking.This work is elegant, simple, and very sophisticated. This is like Soshu-Denfs best master work, and there are nie which are dark and pale and contrast with the nioiguchi, and one never gets tired of looking at this. 

This is a distinctive Meito with a dynamic shape, a subtle and profound classic hamon, and very sophisticated style and as you can recognize, Tsugutada was a very highly skilled master smith.


Explanation and picture by Ishii Akira.





No.707 Tosogu Kanshou

Juyo Tosogu


Botan shishi zu ( peony and lion design) kogai

Mumei: Ko-kinko


A kogai was originally used to adjust a samuraifs hair, and was included in koshirae along with a kozuka, but the origin is unknown. You can see old koshirae examples, such as Itsukushima shrinefs Nashi-ji Kiri-mon raden koshi-gatana classified as Kokuho, and the Mori familyfs Kiku-zukuri koshi-gatana classified as Kokuho, and these works are from no later than the Kamakura period. Both of those kogai have a shakudo-nanako ground with takabori, with an Eda-kikumon and Kiri-mon design. They are very well made, and later become examples for Mino-bori and Iebori-Goto work. Gold smithfs work from before the Momoyama period, which includes kozuka, ko-gai, fuchi-kashira, and menuki, and for which the school or location they come from is not obvious, are called gKo-kinkoh.     

This is a kogai and is judged as Ko-kinko work. The peony with lion design was used on Kamakura period weapons, such as the Nyu-gun Nimitsuhime Shrinefs Hyogo-Gusari tachi which is classified as Juyo Bunkazai, and on the Kasuga Taishafs o-yoroifs egawa (the leather part of the fukigaeshi on the kabuto). Possibly the combination of a brave lion with a gorgeous peony was a warriorfs preference, and later this design was frequently used for toso-gu.

Most of the gold inlay on the ko-gai is rubbed and gone, and only the gold on the edge is left. However, its patina and aged appearance, the deep copper rust on the tsubafs surface, and the yamagane color all match well, and it has a graceful feeling. Also, the nanako grain sizes are unevenly large and small, with no special tecnique or pattern apparent, and is very natural appearing , and this work has a classic feeling. 


Explanation by Iida Toshihisa




Shijo Kantei To No. 708


The deadline to submit answers for the No. 708 issuefs Shijo Kantei To is February  5, 2016. Each person may submit one vote. Submissions should contain your name and address and be sent to the NBTHK Shijo Kantei. You can use the Shijo Kantei card which is attached in this magagzine. Votes postmarked on or before Feburary 5, 2016 will be accepted. If there are swordsmiths with the same name in different schools, please write the school or prefecture, and if the swordsmith was active for more than one generation, please indicate a specific generation.




Type: tanto


Length: 8 sun 5.5 bu (25.9 cm)

Sori: uchizori

Motohaba: 6 bu 6 rin (2.0 cm)

Motokasane: 2 bu (0. 6 cm)

Nakago length: 3 sun 2 bu ( 9.7 cm)

Nakago sori: none


 This is a hira-zukuri tanto with an ihorimune, an almost standard length, and which is thick for the width, and there is uchi-sori. The jihada is a well forged tight masame hada. There are dense ji-nie, fine chikei, bo-utsuri and a clear jihada. The hamon and boshi are as seen in the picture. The hamon habuchi has hotsure, nijuba, and kuichigaiba. There are frequent bright and clear nie, kinsuji and fine sunagashi. The nakago is ubu, the nakago tip is saki-kiri. The yasurime are the schoolfs unique yasurime, and there are two mekugi ana. On the omote side, there is a signature.




Shijo Kantei To No. 706 (in the November, 2015 issue)

The answer for the Shijo Kantei To No. 706 in the November

issue is a tachi by Osafune Hidemitsu, dated Meitoku 3.


This tachi has a standard width, and the the widths at the moto and saki are different. There is a large koshizori with funbari, the tip has sori, and there is a chu-kissaki, and this type of shape is often seen around the end of the Nambokucho period. Hidemitsu is classified as a member of the Kosori group. His jihada are itame mixed with mokume and nagarehada, and the hada is visible. There are thick kawari-tetsu type chikei (formed out of more than one layer of steel), jifu, and midare-utsuri, which is a characteristic Kosori jihada.

The Kosori hamon are based on ko-notare and ko-gunome just like this tachi, and there is a continuous round top ko-gunome hamon like Yoshii work. There are  many types of hamon elements mixed together such as ko-gunome, ko-choji, ko-togariba, square gunome, kataochi-gunome, and ko-notare and uneven midare hamon. This hamon is very low for the width of the blade, and is basically a small hamon. Many of the schoolfs boshi are midarekomi and have togari.

Early Kosori work can be described as having a shape in the Enbun Joji style, and having a dynamic shape. The jihada are a tight itame; the hamon are based on kaku-gunome mixed with togariba, and there are ko-notare and kataochi style gunome hamon, or a ko-notare mixed with small sized gunome, square gunome, and togariba. The boshi are midarekomi, and the tips are togari-like.

At the peak of the Nanbokucho period, the Kosori hamon often bear a little resemblance to Osafune Kanemitsufs and Motoshigefs hamon, but the midare patterns are a little uneven. There are typical examples dated Joji 4 (1365) by Nariie and a dated Oan 4 (1371) Hidemitsu sword, and both are classified as Juyo Bunkazai.

Beside this sword, Hidemitsu has a Juyo Token classified ko-tachi dated Oan 5 (1372). There is also a tachi with an Enbun-Joji style large kissaki, and the hamon is based on gunome and choji. I have never seen this sword and can not confirm its appearance, but this seems to appear like an early Kosori work.

After the Eiwa period (1375-1378), the narrow tachi shape appears to be prominent in typical typical Kosori work, and one could say this is a characteristic point of the entire Kosori school.

In voting, the majority of people voted for Kosori smiths such as Moromitsu, Iemori, and Tsunehiro.The Kosori smithsf works are similar to each other, and it is difficult to identify individual names, so any Kosori smithfs name is treated as a correct anwer at this time.

The Oei Bizen smiths Morimitsu and Iesuke have Kosori type work before Oei 10, and if people explained about this, we treated this as a correct anwer.

Around mid-January, about the time that you will receive this magazine, the special exhibition which was shown at the NBTHK until early November gBizen Token Okoku (kingdom)h will be shown in a second location at the Sano museum in MishimaD

At the Sano museum, there are many Kokuko and Juyo Bunkazai swords, all of them are Bizen master works from the end of the Heian period to the early Kamakura period to the latter half of the Muromachi period. As part of this gBizen Token O-kokuh theme, Kosori work is also being shown.

Until now, there were not many serious studies of Kosori work. The special exhibit catalogue lists the NBTHK curator Imoto Yukifs paper titled gConsideration of Kosori smithsh. Conventionaly, Kosori studies have not been pursued consistently until now. Imoto investigated this school and explained many of his his opinions, and I think his study was well done.  

If you go to the exhibit, read his paper, and at the same time look at the exhibit. You would enjoy those efforts.              


Explanation by Hinohara Dai