Lewis B

If it was this one (99% sure) then seller was taking a huge loss. Asking price was 45 million back in Jan.

I think this more than the actual asking price was what really caught my attention. I would have to assume that at some point an attempt at TJ was made (Kotetsu blades have passed TJ) and failed. AOI (its not stated that this is a consignment piece so therefore part of the company inventory) seems to be capitalizing on the Kotetsu hype train.

I should have qualified the OP as Nihonto without historical figure connections, or outlier, head scratcher Christies/Sothebys/Bonhams results.

https://sword-auction.com/en/product/26439/as25067-katana-nagasone-okisato-nyudo-kotetsu-with-saidan-mei45th-nbthk-juyo-token/

Yes, and even saiha pass Juyo in rare cases. I bet this is a case of buyers remorse. That blade looks rough and tired. Still a lot cheaper than the 22mil Yen paid for the dubious condition TJ recently.

Very nice. I could almost guarantee this seller has multiple Ebay/Yahoo sellers accounts. The photos are just too well executed to be a noob on the scene. They are some of the best I've come across on those platforms. I would assume its gimei. There are kanji by 2 different hands on the omote. The bottom two appear older. The koshirae fittings also appear above average and can I detect a signature on the tsuba? Hard to tell for sure with all the patination. Overall if you like the blade its worth a punt at that price. The hamon seems quite distinctive so maybe this can be the subject for further research on the maker.

Waiting for Jacques to say thats not green, its lime.

The smith almost had a heart attack when May was reaching for the blade with his left hand.

Nice example of a saiha Shintogo Kunimitsu tanto, retempered by Echizen Yasutsugu (1st Gen) and passing Juyo. Hideyoshi owned.

A swing and a miss. Again. You are choosing examples that prove your point. What you refuse to see are the examples above that have different style of boshi such that if the blade was modified to naginata-naoshi, a small kaeri could be retained.

OP doesn't own the sword or have access to it to take better pictures, but your point is well made. Taking good, informative photos is critical on a forum like the NMB to appreciate the blades details. It's half the fun.

@Brano excellent examples of why taking carefully executed photos, under sympathetic lighting is so important. The finer details come alive and can be appreciated when in hand examination is not possible.

This is a modern gendaito maker so why would he put a mekugi-ana through his Mei. The style of nakago and Mei appear problematic. What is the nagasa measurement?

And another. A Juyo naginata naoshi attributed to Kashu Sanekage from the Nanbokucho era. The kaeri is absent on the ura side.

Yes, and they also have a bridge listed. Just look at the nakago and you'll see this is more like a blade from the 1920's than 1290's

This is a great resource, especially for those new to Nihonto collecting. Thanks for posting.

That bend,,, ouch

The carving is spectacular as you would expect from this maker.

Ubu yet mumei? An interesting discussion here around the subject. https://www.militaria.co.za/nmb/topic/14981-ubu-and-mumei/#comments

The koshire (especially the ray skin saya) is very fine. This suggests the blade for which it was made is equally valuable. Being mumei and o-suriage I would assume its quite old (family blade?)

Looks to have a kirikomi on one side of the mune. Can't quite figure out if it has shintetsu along a section of the hada. But Tanobe sensei seems to like it.

That 47g solid gold habaki is worth almost $5K in scrap gold value alone.

Not sure if everyone will have access to the 2024 source paper linked by @AlexiG and the authors hypothesis regarding Utsuri and its appearance on Nihonto. So I will post a link here. While still conjecture on the part of the authors its good to see an hypothesis examined in detail with scientific data and for the paper (I assume) to be peer reviewed before publication. As to why its present I agree with others here who say that for the most part it was not by accident. Without access to metallurgical testing the early smiths would have known which blades stood up to a beating in battle and those that failed, merely from a visual examination. It wouldn't take many examples to make the connection that a blade with Utsuri was more resilient (which appears to be the case) and for Utsuri to be 'engineered' into the blade to recreate those favourable characteristics of durability as an evolution, over decades and centuries, into the swordmaking process. As to why the appearance of Utsuri diminished going into the Edo period, that could be related to a shift from a focus on durability to one of aesthetics ie jihada and hamon. Far easier to appreciate a beautiful hamon line than ethereal Utsuri clouds. Utsuri paper.pdf

Load onto a Google Drive folder (no file size limits) and post the link.

Yet it has TH papers. That surprises me.