NBTHK tachi vs katana

[drl]

After having reviewed many NBTHK papers in my current quest for a pre-Edo tachi, I've noticed many examples of papers that list "1. Katana" and others that list "1. Tachi".  However, I haven't been able to figure out what causes the NBTHK to paper a blade as one versus the other, *except* that I noticed virtually all blades from the late Edo period or after seem to be papered as katana, not tachi.

 

But I've seen many blades from 1200s, 1300s, and beyond that are papered as tachi or as katana even though they are:

- mumei, or signed

- signed tachi-mei, or signed katana-mei

- > 70 cm, or under 70 cm

- pronounced sori, or less sori

- ubu, suriage, or o-suriage

- from a variety of schools and styles

 

Is there a clear logic to the NBTHK decision to paper as katana vs as tachi?  

 

Thank you for enlightening me.

[Ken-Hawaii]

There is a clear logic, although the timing is a bit vague. Prior to Muromachi, all blades were tachi. Why? Because one way to define a blade is how it was used. A tachi was worn edge down. During Muromachi, battle techniques changed, blades got shorter, & began to be worn edge up, which defines a katana.

 

When a blade's mei is on the omote nakago, it's signed as a katana, but if it's worn as a tachi, it would be considered as tachi. So you can see that the terminology isn't as definitive as it is descriptive.

[Toryu2020]

David -

It goes pretty much as Ken has said - early blades are assumed to be tachi - UNLESS they have been cut down into katana or wakizashi - then the paper will say katana/wakizashi even though everyone knows it started life as a tachi.

Post 1600 - every blade is assumed to be a katana - even with tachi mei (think Hizen) - UNLESS the general practice of the smith was to sign katana mei but you get a one off tachi mei (as happens in Shinshinto)

 

These were the rules explained to me by a Shibu-Cho of the Kamakura Branch of the NBTHK - but he went on to say there was a period when the NBTHK started calling obviously early blades tachi even though they were osuriage mumei - this went on for a time and now we're back to the rule as stated above. Like everything else in Nihonto, "The rules are easy the exceptions are what will kill you..."

-tch

 

[Rivkin]

I would argue the difference between the two gets over-emphasized in english language sources. Usually just the kanji for "to" or "daito" is being used. 95% of Japanese would read it as "katana" and would be surprised to hear "daito". In the collector's circles on the contrary "daito" versus "shoto" is a common reading, while I personally have not heard "tachi" being used too often.

[drl]

Thanks for your helpful replies.  Here are some examples—all sold as tachi—of what I find confusing, or at least not consistent:

 

Tokubetsu Juyo from mid-Kamakura (~1299), 72 cm, o-suriage, papered as katana (I assume because of the o-suriage?)

https://www.aoijapan.com/tachi-mumeirai-kunitoshi/

 

Tokubetsu Kicho from early Muromachi (~1398), 71 cm, ubu (?), papered as katana

https://www.nipponto.co.jp/swords6/KT332998.htm

 

Juyo, mid-Kamakura, 73 cm, suriage, papered as tachi (meaning dai to)

https://katananokura.jp/SHOP/1203-TC01.html

 

Juyo, Nanbokucho period (~1362), 71 cm, ubu, papered as tachi

https://www.sanmei.com/contents/media/S35492_S830_PUP_E.html

 

Tokubetsu Hozon, late Nanbokucho, 75 cm, suriage, papered as tachi

https://nihontoart.com/shop/tachi-signed-akikuni/

[Toryu2020]

Thats just it - the rules are simple the exceptions are legion...

-t

[Jussi Ekholm]

As far as signed tachi go, Aoe school as well as Hōju school were sometimes writing on opposite side that was commonly used, there are some other exceptions too. However as they are generally very old swords they were made as tachi regardless of the side of the signature. Well one could argue that in some cases there would be 0 difference between some tachi and katana (if size and shape are looked at) and they would be correct.

 

For mumei I think in general if the alteration to nakago is only slight NBTHK will classify it as tachi if it retains enough of it's original shape.

 

I think the Mumei Ichimonji example (3rd one on those you listed) has me puzzled. NBTHK mentions it is almost ubu, and their expertise is far greater than mine. However it appears to me to have been shortened some amount. It is puzzling...

Here is a mumei example attributed to Ayanokōji school tachi and nakago is almost ubu, only very slight alteration: https://www.aoijapan.com/katana-mumei-attributed-as-ayanoko-ji-ntbhk-the-43th-juyo-token/

 

I think the only complicated divider would be when a tachi is mumei and slightly altered. If it would be accepted as almost ubu it will still achieve it's classification as tachi, however if a mumei sword is deemed suriage then it will be classified as katana. There is also a term slight suriage that NBTHK sometimes uses that is sitting just about at this dividing point. I can try to look into the NBTHK Jūyō papers more closely tomorrow, this is just from the top of my head.

 

I think the den Nobukuni example is very interesting one. It was papered with old system and I would think of it as a tachi from possibly early Muromachi period. I am looking at the picture and trying to figure out if it had had possibly a signature removed. I am not a gambling man but that could be nice one to look closer, however I think the 1,8M asking price drives me away.