Family Heirloom Koto Blade WW2 Naval Wakizashi

[Rhizosphere]

Japanese traditionally made family heirloom wakizashi.

I was informed this was a Koto blade and forged in the early 1600s. Used as a naval officer's sword and, potentially, as a pilot's sword in WW2.

The blade measures 21.5 inches. Bares a naval sharkskin saya. But retains its original Samurai mountings (potentially re-wrapped ito?) The tsuba. I think may be Tosho and predate the sword. The tsuba is meticulously hand carved (jumping lion and rose bush?). And has nanako surfacing on both side. There is also what looks like gold foil inlay in the handle (resembling a catfish and clouds). Which has partially flaked off. The blade also has a 2 piece 2 tone copper habaki. There is also evidence of what may be a defensive blade strike in the defensive zone (lower quadrant) of the blade. Potentiallly has kitikomi im in one spot on the spine (Photos at the end). Along with very small scratches in one area on either side of the front side of the blade. Upon very close examination. I have found a few other small indentations in the blade edge. Which may have been polished out. The blade is sharpened to the habaki.

 

The Hada I would describe as "Itame with areas that resemble "O-Mokume". The "Suguha" hamon exihibits thick "Masame"hada with specks of nie. Along with streaks of nie and noi. With a bit of a reflection of itself hovering above the main temper line. Which consists of a darker band of, is it martensite? Followed by a thin sparkly band of Nie.

 

The blade is supposedly signed by the 1st generation Tadayoshi. It reads  肥前國住忠吉作 ("Hizen no Kuni Ju Tadayoshi Saku"). But I believe it was most likely signed by an approved student. I do see inconsistencies in the mei. The kanji for Hizen is written with the dash mark inside, not out to the right. But interestingly. It is a horizontaI dash as the Tadayoshi school wrote. Not a slightly angled vertical dash as Hizen is properly written. Maybe placement had to do with the area the smith had to work with? I have read that swordsmiths at large schools would have approved students make blades for them. But it could just be completely gimei. There appears to be remnants of some sort of inlay in the mei. But the bare steel underneath, which can be observed in the mei, is the proper color and oxidization as the rest of the tang. So I assume it was done at or around the time of its forging

 

I was also informed the blade is more Bizen NOT Hizen. But I have also read that the Tadayoshi school did produce some Bizen replica blades early on.

 

My questions are. What do you think of my analysis? Quality of the blade, hamon, hada? What period do you believe it is from, along with the tsuba? And what are your thoughts on many of these gimie Tadayoshi signatures actually being from students or close relations of the school approved to make swords? Could this sword have been mumei that was recognised as Tadayoshi and signed then? The blade and mounts speak for themselves. I believe it lends towards the blade being of fine quality. Or at least who mounted it thought so.

Notes: Included photos of every inch of the blade. Up close areas of interest in the hada and hamon. The signature, polisher's marks and potential signs of use. This is my 2nd sword and 1st traditionally made blade. I am still learning the ins and outs. I am not upset for it to be gimie. The blade itself and mounts are fantastic. I am just looking for people to discuss it with and give me their thoughts.

 Thanks for your time.

Edited December 24, 2025 by Rhizosphere
1 typo

[ChrisW]

I'm not sure I am seeing the Bizen assertion here. If Roger Robertshaw said that, then shows what I know! He is pretty much the expert on Hizento. Wherein the US are you located?

Looks Hizento to me. Has a very stout appearance to me with a proper Hizen-style nakago. Thin kawane (there is loose grain/possible core steel showing) which is an indication of a Hizen blade as they are made with very thin skin steel.

I can't speak to the veracity of the signature; but you have a decent example of a Hizento at the very least. 

[Rhizosphere]

I am not sure who the person you referenced is, apologies. It was told to me by a person on instagram after they viewed a couple photos. But he didnt seem interested in answering questions so I assume he didn't give it a good look anyway.

[Ian B3HR2UH]

Sorry to be blunt on Xmas day but here goes I am afraid . It doesn't look at all Hizen like and the mei is way , way off . If the signature was cut by a student then it would have some passing resemblance to that of the person he was cutting it for but this is just gimei and a bad one at that .

 

[Rhizosphere]

7 minutes ago, Ian B3HR2UH said:

Sorry to be blunt on Xmas day but here goes I am afraid . It doesn't look at all Hizen like and the mei is way , way off . If the signature was cut by a student then it would have some passing resemblance to that of the person he was cutting it for but this is just gimei and a bad one at that .

 

What makes you think it isn't Hizen? It is hard to understand these points without areas to reference. 

[Rhizosphere]

1 hour ago, ChrisW said:

I'm not sure I am seeing the Bizen assertion here. If Roger Robertshaw said that, then shows what I know! He is pretty much the expert on Hizento. Wherein the US are you located?

Looks Hizento to me. Has a very stout appearance to me with a proper Hizen-style nakago. Thin kawane (there is loose grain/possible core steel showing) which is an indication of a Hizen blade as they are made with very thin skin steel.

I can't speak to the veracity of the signature; but you have a decent example of a Hizento at the very least. 

Located near St. Louis btw

[Rawa]

Only saya matches as to be kai gunto koshirae.

Tsuba imo not carved but casted. Ko kinko’ish but nagoya mono - „casted for shelf”/tourist piece.

Made from yamagane.

https://kevinpage.co.uk/stock/ajapanese-meiji-period-iron-tsuba-with-multimetal-fo-dog-design/#panel1d

 

Edited December 24, 2025 by Rawa

[Rhizosphere]

19 minutes ago, Rawa said:

Only saya matches as to be kai gunto koshirae.

Tsuba imo not carved but casted. Ko kinko?

https://kevinpage.co.uk/stock/ajapanese-meiji-period-iron-tsuba-with-multimetal-fo-dog-design/#panel1d

So is the sword not 1600s at all???

[Rhizosphere]

20 minutes ago, Rawa said:

Only saya matches as to be kai gunto koshirae.

Tsuba imo not carved but casted. Ko kinko?

https://kevinpage.co.uk/stock/ajapanese-meiji-period-iron-tsuba-with-multimetal-fo-dog-design/#panel1d

And what do you believe the value of this blade is?

[ROKUJURO]

TSUBA is probably NAGOYA MONO. FUCHI-GASHIRA have suffered some corrosion, but MENUKI look interesting (but you never know until they come out....).

Jimmy, as for TADAYOSHI signatures, just look for certified examples and compare.

[Rawa]

Just now, Rhizosphere said:

And what do you believe the value of this blade is?

Blade was once polished with care [9 nagashi lines under habaki]. But I see shintetsu here so it is old tired tamahagane.

I can’t estimate value but it’s wakizashi so You should wait some years with selling this. Dr @Rivkin maybe would correct me about quality of this piece

[Rhizosphere]

Just now, ROKUJURO said:

TSUBA is probably NAGOYA MONO. FUCHI-GASHIRA have suffered some corrosion, but MENUKI look interesting (but you never know until they come out....).

Jimmy, as for TADAYOSHI signatures, just look for certified examples and compare.

I'm sure it is gimei. But I'm not really too concerned about that. I'm more into the blade and how it presents. And see what others think. I imagine it as mumei. 

[Rhizosphere]

1 minute ago, Rawa said:

Blade was once polished with care [9 nagashi lines under habaki]. But I see shintetsu here so it is old tired tamahagane.

I can’t estimate value but it’s wakizashi so You should wait some years with selling this. Dr @Rivkin maybe would correct me about quality of this piece

Thanks for the info. I got it thinking of it as mumei. And to just admire the blade. The price seemed correct for a traditionally made wakizashi in good condition. Maybe consider selling in the future. What is your signature that the blade is tired and polished many times?

[Ian B3HR2UH]

Your grain is pretty open and rough , If you type Konuka hada into a search engine you will see what Hizen hada should look like

[Rhizosphere]

3 minutes ago, Ian B3HR2UH said:

Your grain is pretty open and rough , If you type Konuka hada into a search engine you will see what Hizen hada should look like

Yes. This was the one defining charateristics that stood out to me as different.

[Rawa]

Even with this angle you can see dark patches and many pits. Like when polishing granite you can „tear out” softer grain.

[Rhizosphere]

2 minutes ago, Rawa said:

Even with this angle you can see dark patches and many pits. Like when polishing granite you can „tear out” softer grain.

So that means it was probably used and polished many times?

[Rawa]

4 minutes ago, Rhizosphere said:

So that means it was probably used and polished many times?

Check shintetsu - kizu, imo book example.

https://www.japaneseswordindex.com/kizu.htm

But still tsukamaki looks nice. Kinda put from parts koshirae. But these parts aren’t worthless.

Even saya is fully covered in ray skin with nice gilding left on elements. Check if there is hole for chuso in koiguchi - it will answer some questions.
 

Edited December 24, 2025 by Rawa

[Rhizosphere]

9 minutes ago, Rawa said:

Check shintetsu - kizu, imo book example.

https://www.japaneseswordindex.com/kizu.htm

But still tsukamaki looks nice. Kinda put from parts koshirae. But these parts aren’t worthless.

Even saya is fully covered in ray skin with nice gilding left on elements. Check if there is hole for chuso in koiguchi - it will answer some questions.
 

No. None. Inside of wooden saya is a bit worn out. Wood shavings come out every time i remove the sword. The sword no longer fits snugly. But the throat matches the habiki width if it wasnt worn down. 

[Rhizosphere]

13 minutes ago, Rawa said:

Check shintetsu - kizu, imo book example.

https://www.japaneseswordindex.com/kizu.htm

But still tsukamaki looks nice. Kinda put from parts koshirae. But these parts aren’t worthless.

Even saya is fully covered in ray skin with nice gilding left on elements. Check if there is hole for chuso in koiguchi - it will answer some questions.
 

Totally shinetsu lol. It's been around the block a bit. 

[Rawa]

Maybe tell how much you have it. If it isn’t originally made to fit blade just forcibly matches sori.

1 minute ago, Rhizosphere said:

No. None. Inside of wooden saya is a bit worn out. Wood shavings come out every time i remove the sword. The sword no longer fits snugly. But the throat matches the habiki width if it wasnt worn down. 

 

Edited December 24, 2025 by Rawa

[Rhizosphere]

8 minutes ago, Rawa said:

Maybe tell how much you have it. If it isn’t originally made to fit blade just forcibly matches sori.

 

How much I have it? The sori seems to match when held next to the blade. It doesnt appear to be carved out. I can share a photo. 

[Rawa]

Just now, Rhizosphere said:

How much I have it? The sori seems to match when held next to the blade. It doesnt appear to be carved out. I can share a photo. 

How long* omg it’s 12p.m. 

[Rhizosphere]

3 minutes ago, Rawa said:

How long* omg it’s 12p.m. 

I just recieved it. Here is a photo. It looks like it may not be the original saya. There is some space. Unles it wore down that much. It matches width wise. But not length.

[Rhizosphere]

10 minutes ago, Rawa said:

How long* omg it’s 12p.m. 

Seems to line up by the fitting at the base strikes me as weird. 

[ROKUJURO]

31 minutes ago, Rhizosphere said:

..... Inside of wooden saya is a bit worn out. Wood shavings come out every time i remove the sword. The sword no longer fits snugly. But the throat matches the habiki width if it wasnt worn down. 

That sounds like a clear indication for a SAYA that had been worked on to fit a 'new' blade. As was said earlier, sellers often put swords together from parts, and the easy part is inventing a good story to push the sale.

A MUMEI EDO period WAKIZASHI is not a good investment, a clear GIMEI one is still less so. But whatever we comment, it is a complete and authentic Japanese sword, and if you like it, don't look at value or age!

And in the long range, you could always replace TSUBA and FUCHI-GASHIRA with nicer parts, and even try to find a fitting civilian WAKIZASHI SAYA.

[Rhizosphere]

3 minutes ago, ROKUJURO said:

That sounds like a clear indication for a SAYA that had been worked on to fit a 'new' blade. As was said earlier, sellers often put swords together from parts, and the easy part is inventing a good story to push the sale.

A MUMEI EDO period WAKIZASHI is not a good investment, a clear GIMEI one is still less so. But whatever we comment, it is a complete and authentic Japanese sword, and if you like it, don't look a value or age!

What would you say the general age is? It isn't Koto then?

[Rhizosphere]

6 minutes ago, ROKUJURO said:

That sounds like a clear indication for a SAYA that had been worked on to fit a 'new' blade. As was said earlier, sellers often put swords together from parts, and the easy part is inventing a good story to push the sale.

A MUMEI EDO period WAKIZASHI is not a good investment, a clear GIMEI one is still less so. But whatever we comment, it is a complete and authentic Japanese sword, and if you like it, don't look at value or age!

And in the long range, you could always replace TSUBA and FUCHI-GASHIRA with nicer parts, and even try to find a fitting civilian WAKIZASHI SAYA.

He does except returns. I paid $1400. Did i get ripped off. Part of the reason I bought it is because I thought it had WW2 history along with being a real Japanese sword. I do want to collect tsuba though. Is it easy find one that fits. Along with saya? Seems difficult. 

[ROKUJURO]

Jimmy,

age is not important, but quality is. You can find very expensive high-quality blades from 1800, and quite shabby blades fron KOTO era.

To make a guess, one should see a blade in hand, but my impression from your good photos is early EDO. But I am more a TSUBA guy so please take my words lightly.  

[Rhizosphere]

3 minutes ago, ROKUJURO said:

Jimmy,

age is not important, but quality is. You can find very expensive high-quality blades from 1800, and quite shabby blades fron KOTO era.

To make a guess, one should see a blade in hand, but my impression from your good photos is early EDO. But I am more a TSUBA guy so please take my words lightly.  

Im trying to be happy with it. Having to adjust what I thought was interesting about it now. And considering the cost and effort of buying and selling parts to make it look correct.