Rivkin

I actually meant itame when mentioned masame in one portion of the original message. Kantei features have sort of weight assigned to them. And koshi-zori has a very significant one. Its presence in most circumstances excludes post-koto. Especially when its well proportioned with an appropriate taper and kissaki size. I don't think its kozori. This being said in the pre-1540 Muromachi that looks like that there are other options besides Omiya. Kaga Kiyomitsu should be given consideration as well as Bungo Takada. Masame in shinogi ji generally hints towards Kaga or Takada.

I am not good with generalities, but I would start with stating that mid Kamakura blades... are not judged by sugata. There is per se no such thing as mid Kamakura sugata. For reasons which are not well understood among the blades attributable to mid Kamakura you find plenty of wide ones with uniform and centered curvature and there are even some o-kissaki examples... and there are more "plain Kamakura" koshi-zori, and there are essentially katanas (known as kodachi) and this is not even going into bizarre Rai Kunitoshi's things in hirazukuri or waki form. Almost anything placed by sugata to mid Kamakura can be placed by sugata somewhere else as well. If it does not have ko kissaki or ikubi kissaki, things not commonly adopted ever since, any koshi-zori blade can easily be roughly first half of Muromachi or the last couple of decades of Nambokucho etc. The photographs do not show either jigane or the hamon well enough for my standards. I just don't see much there. The tops of choji or gunome in Kagemitsu school are often squarish and that's what one often finds in Omiya. Their jigane is a bit rough and expected to have large featured mokume and masame elements but mostly itame based. Their utsuri is seldom spectacular and is often absent. However their nioguchi is often bright, and there are activities like sunagashi and overall tint of nie in the hamon which make their work bright and attractive or even move the attribution to Soden Bizen or Fukuoka Ichimonji. I don't know exactly what is seen here. Sukesada is quite different in most aspects.

I don't think any stamp was designed as proof of the manufacturing method. They indicate a type of maker or a certain path or "agency" through which the blade was supplied to the military. Those designed for inexpensive suppliers will deal mostly with showato, those with more pricy items will tend towards gendaito. It needs to be said that in this context gendaito does not mean something made 100% in accordance to the current legal standard, which was unknown at the time. A blade with good jigane will be called gendaito, but it might have only 50% tamahagane and 50% some other steel(s). etc.etc.etc.

Well, this would be reasonably expensive if it papered by NBTHK, so my guess it failed NBTHK and maybe NTHK then marked it as gimei but added an opinion that it's Munetsugu and Kurashiki paper was the last resort. But its actually very convincing - Kiyomitsu did work in this style and I am not surprised if it was actually submitted to all three papers. There are things that do not look like Kiyomitsu - jigane is off (which was probably the main factor in the judgement), there is no bo utsuri... Kiyomitsu tanto often have itame, but its very well grained somewhat larger and ji nie is much brighter, it comes out a lot even when photographed from above. He also did some more coarse-Muromachi typical jigane, but usually on daito. This jigane is too dense and bleak. I don't want to check the books but the signature-nakago looks impressive.

I think such statement would be based on the blade acitivity rather than signature alone. One thing I appreciate with active seller's listing is having a link to it. I understand many are afraid someone else will snatch the offer but it seldom happens and it saves a lot of time. Koyama Munetsugu has a distinctive style quite different from Kiyomitsu, despite the latter being unusually broad in his own output.

Yes. I will join the above statement that its Monju.

Not uncommon especially with things like Sadamune where the notion "it is THE Sadamune" is important.

I papered this one around 2012 or so I think.

It is indeed shaped like Kambun shinto blade, but the work and the signature are puzzling. Sukesada did notare but still with an indication its a Bizen blade, which is sort of not obvious here. His signature is deep, straight, condensed (i.e. if you draw rectangles around the kanji the strokes will enter neighboring borders) and powerful. Here its weak, spaced and quite a bit more cursive. I vote gimei.

Yet another Kiyomaro wanna be with very dense hada.. Most likely the very end of shinshinto or early showa.

Looks like Mino-ish late Muromachi waki. Not too much of a collectible but authentic, so the only question is it fun enough for you.

Not much is known about Mogusa. He is referenced in 13th century texts as 11th century smith, but his fame gradually decreased since then. Today there are no certainly identifiable examples and the name is used as synonym of Houju, which in turn are mostly Nambokucho-Oei period attributions. It is often stated they were made in Hiraizumi, but no evidence of such exists and the city itself did not exist in Nambokucho until it was reinvented/rebuild in the 19th century as a tourist site.

Need the overall photo and much better pictures of the activity. Cell in one hand sword in the other does not work.

Ordering habaki, shirasaya, koshirae, polish is fun but best done on a blade which is appreciable and of good promise. Can still be 1000$ blade, but it needs to be without major issues.

Generally any investment in unsigned Edo period's piece restoration is not financially advisable and more so when its unpolished waki.

The tip sticks up a bit too abruptly for 1350. Maybe late Muromachi.

One more option: Its been quite a while and I can't find the photograph so I am not sure about the details (!) - but I think I had at one point nijimei Kunitoshi tanto which papered NBTHK with an explicit statement it was Muromachi period's. The problem I don't remember it might have been Kunimitsu or Kuniyuki - what I do remember it was a top Rai name and the signature was clearly styled after the "real one", but still the shinsa did not want to reject the notion Muromachi's smith might have had the same name as well.

I would start by submitting it for papers. I am not at all knowledgeable on Kunitoshi's signature and I am not crazy about this nakago, but the sugata is more or less within the possible (though not of the most distinctive type) and also what little is seen of the work (second image) is very strong. I would check if boshi looks correct though (can't see). I would have doubts if its Kunitoshi, but it is within the realm of theoretically plausible and even if its judged as gimei I personally would strongly consider going with this blade as a restoration project.

Definitely would be a show stopper for me. Its not old enough to have fukure.

Sorry I missed that. I would argue that such extensive muneyaki is Soshu trait and was adopted from it by other schools of the period. But in 1540-1580 one sees such "eclectics" quite often. Still there is a chance its not Bizen... In any case it looks from what little is seen is that its a good blade. Are there kizu? If there is none, even though commercially its not that viable, still polish can potentially reveal a very good blade.

I have to admit the measurements are seldom exciting to me, but having a dedicated shot of the boshi and the nakago is usually a must. As is the overall shot from above and at least something on the activity. Since statistically pretty much 95% of what is seen are average blades from Tembun Muromachi, Kambun Shinto or Showa this can be sufficient.

In Marcus' book there is SADASUKE (定祐), Kanbun (寛文, 1661-1673), Yamashiro – “Yamashiro no Kuni Kurama-jū Sadauke” (山城国 鞍馬住定祐), Sue-Seki style But I indeed would vote for unrecorded Bizen guy from around 1540. Unless it has sugu boshi, which is not that well seen here.

I think its an interesting and authentic object but its not Japanese per se. Not an expert on SEA weapons, but one does see very large nagamaki like weapons in the region with Japanese styled blades.

Ogh, very fat, straight with some small taper... Even though its a waki, Kambun shinto is a likely option. Better guess needs closeup of boshi, nakago and activity.

Depends on what can be seen on the blade itself with a naked eye.