Rivkin

The shape is common in some traditions depicting "ancient" daggers. 19th century influence.

Nice blade, late Muromachi, but otherwise it starts to get weird. Could be Bizen, but mitsumune and nakago are uncommon for the school. Looks very much like Mihara, but again mitsumune is not common. On the other hand, tensho period's Odawara did work in suguha a lot, can be a good match.

My answer would be "its extremely complicated". Even discarding the impact of polish, which however is quite large when it comes to nioiguchi, nioiguchi physically demonstrates the temperature gradient due to heat conduction between the portion of steel that is cooled directly by water and the portion which is cooled slowly through clay. So theoretically a very clean steel will give you a tight and bright nioiguchi while slag will create something hazy and uneven. But its not exactly true. First, the forging comes into play as heat conduction within lamination is always higher than between laminations - so if the blade is itame you can have tight and bright nioiguchi (Yamashiro), if it has mokume or masame going in and out hamon nioiguchi there is good chance is not going to be as well defined. Second, daito has quite a lot of material at habuchi level and thus will cool down slower compared to tanto. So tanto with all conditions even will have different (and often brighter) nioiguchi compared to daito, and daito with niku will have broader nioguchi compared to something thin, and if there is a core iron which has some other thermal resistance (usually it does), then two piece sword will have tighter and brighter nioguchi compared to a single piece work... By the same token controlling hardening is usually easier for tanto and for the same amount of nie on daito the margin for error is considerebly smaller.

Nioguchi is not a factor for Hosho. Best Hosho has a lot of chikei, hamon which has strong and bright nie formation, hada with very bright jinie, both masame and itame. Its not as uniform as Sendai or some shinshinto blades, but the non-uniformity adds character, its not awkward or artificial.

Just one: do not read Facts and Fundamentals. He has his system which is based on very obscure things... It works for some blades, but not for others. Lots of Hasebe and Masamune will not have a "quality nioiguchi", in fact it can be quite difficult to observe. There are some Yamashiro and Bizen blades which can be judged by nioiguchi but even then Hizen's very wide nioguchi is not a sign of issues anymore than very tight nioguchi... Brightness counts more, though again his school insists that if its too bright then its acid etched etc. etc. Hosho is very good, as are some Kiyondo and even some Kunikane.

1. The title is wrong. 2. The blade definitely looks like Muromachi Bizen. 3. It seems to be dated/signed but without really large photos its hard to verify the authenticity and frankly its a bit of a bother. So yes, its authentic Muromachi Bizen, the signature could be right could be not, these things are surprisingly often faked. 3800$ is a lot. You can buy decent muromachi daito with mounts for 4000 today.

It depends on the budget. In the best case the strategy is to simply walkin to Sokendo shop, give an attendant a list of what you want to see, tell him you have a budget ready and ask if Kurokawa san can show you the blades. He has an encyclopedic collection so you will see a really good Unshu if you want. Basically if you are in Japan and comfortable buying there (no returns, in most cases incomplete disclosures and some chance of outright lies), you should buy there. If you want moneyback or some other conditions, US is an option, but aside from sword shows its going to be more expensive.

Swords are bad investments. Dealers will tell you otherwise. Unju is a good school, if anything its undervalued. However with the current yen rate 6 million yen is a lot of money for Unju Juyo. They are not terribly uncommon. The mounts are authentic but very late (the very end of Edo, less likely Meiji) with a generic 3-5 pawlonia which is quite common, of good quality. Here is 3 mil yen one: https://sword-auction.com/en/product/14907/as22336-刀無銘（雲次）第22回重要刀剣/ Generally 6 mil at a discount shop buys you decent Ichimonji Juyo or really good Aoe, but then at a premier store you might find the same blade for 12 mil, so its all relative.

Hard to be certain but it appears to be late Muromachi piece. Can be Bizen, so "Bizen Sukesada" attribution is a possibility.

I don't know but I can theorize. Its not satsuma suriage but in shinshinto all foreign and weird things were quite popular. Often the problem dealing with local Japanese experts is they want copies of European hussar blades, smallswords, turkish sabers etc. etc. to date from Momoyama and be connected to one of the famous Daimyo, why in reality the vast majority of such copies were made in 1800s. And many are not copies but actual foreign objects. P.S. And maybe its some rare ikebana ninja sword for cutting lotus flowers I just don't know much about.

Unfortunately even without seeing any activity I would not be optimistic. Sugata is awkward, yasurime is deep and well spaced, patination highly uneven, the kanji are poorly written. Its quite recent (probably post Edo) and the quality I would expect to be on a low side. Even shirasaya is weird with its squarish shape which is probably a bit easier to make.

As little can be seen and earlier Tegai being an option, I personally would still vote for sue-Tegai of Muromachi period. The activity is complex and roundish swirls of ko nie are not that common in early blades but are more typical for Muromachi.

Its unlikely to be kodachi and I would abstain from purchasing this blade. Muromachi period most likely, saiha is a possibility, nothing too exciting as it looks. Ko dachi look deeply curved only when drawn on the same page as regular contemporaries.

Possible, still can't figure out with such light... not that important, for late blades mune shape is not absolutely crucial.

The nakago leans towards Kaga land, long kaeri suggests Soshu imitation as is mitsumune, it looks somewhat bland overall, most likely the end of Muromachi or whereabout.

I think one of the greatest problems of kantei books is they give you a clear cut, foolproof certainty example where if you put together all the features its got to be Kanemitsu and no one else, and that's also the reason why oshigata is sufficient for such purposes. In most cases kantei is however probabilistic in the sense that the features are not exclusive to attribution, but are more or less common. So, Hosho hamon tends to be on a narrow side, while Sendai is generally wider. Hosho boshi tends to have shortish kaeri (on tanto there is very often no kaeri), Sendai kaeri can be longer and more detailed. As most shinto nie Sendai nie tends to be of the same size, Hosho varies within the blade. Hosho work tends to be more non-uniform, the width of masame varies, Sendai is very uniform. Hosho hamon tends to have a bit larger and more bright nie, with more variability within so that nijuba and hotsure are very prominent and wide in places, Sendai hamon is a bit more bluish and has thinner hotsure. Some Hosho lineages practice a mixture of masame with Awataguchi level very fine itame, there are some Sendai smiths who could do that as well. Both schools practiced either straight or a bit endulating, sinusoidal masame. Generally sue Hosho (i.e. Muromachi Hosho) is quite uncommon and quality wise is very similar to Hosho, usually judged as such on the basis of sugata alone.

It really depends... From 2 weeks to 7 months. Usually on the short side. For 200,000 I would not worry too much, it will get through just needs time. Unless you don't trust the dealer.

The hada is pure masame, but lacks chikei and very uniform. Hamon does not show nie except at a few specific angles where its obvious it has ko nie. Boshi is very detailed but at the same time not very bright. That really looks like Sendai Kunikane. Quite a few were papered in 1970s as Hosho, some even with sayagaki. That's probably your worst case. The best is yes, Hosho or maybe Shikkakke if the hamon is not pure suguha but has strong notare. But I would be betting on Sendai.

Sorry to hear that, my condolences to the family.

I'm puzzled. Not too comfortable with someone monitoring members PM and then hinting in public about their content. Not crazy about promoting personal issues against someone in such a way that he is easily identifiable, yet not named. Accusing all free member as exploiting the "efforts and knowledge" of other forumites is even stranger. Whose knowledge exactly are we exploiting here? Yours, Brian? Buddies you met at DTI? I switched the membership to free and my exploitmeter is still inactive. I am realizing the endless depths of my personal fallings. I do have a second account. Hope it was not used to seduce minors for swords, or maybe even swords for minors. Painful admission - I did make offers for blades. I did not know there is a ritual that needs to be performed. Full moon, "I've sent a PM" written by bloodied wakizashi in a public section. In general - not good with moralisms. Tend to suspect the money is involved somehow. Hope my account gets deleted with all its messages.

Regretfully I can offer only a late answer: the forum's functionality prevents me from ignoring the entirety of Guido/dealers loyalty club, but I've tried my best and unfortunately missed an important point. Collecting is a bit too expensive a hobby, in every aspect, to undertake unless it improves one's character or abilities. I am obviously an ill suited example of such "improvement", but one of my teachers many years ago used to task us with observing a specific floor of a museum so we would then discuss pluses and minuses of paintings presented, their selection and placement etc. The purpose was to nurture a proper officer core. Modern officer is a sad spectacle - a random figure in search of secure retirement check and sexy uniform, determined to spend his life pushing papers or at worst immolating an enemy at least 1,000 times less significant in resources available to them... Under such circumstances being a proper officer does little save damage one's career, as the main requirement of such, at least according to my teacher, was the ability to develop, adjust and present an opinion even when facing not only enemy's bombardment, but even one's superiors. The sensei was determined to weed of our fears by forcing open arguments on the subject where the rules are as ill defined as the battlefield future and the observations are as objective as battlefield intelligence. The art connoisership. He would punch those who memorized the museum's catalogue, push those fishing for sensei's opinion so they could then present and develop it as their own (arguably the talent of extreme use to one's career), smack those too scared to offer an opinion, since how one discusses good and bad when the rules are not set and you saw the paintings once, and the catalogue is b&w etc.. This last portion was 60% of the class and the first was probably 10%. Obviously my sin was being obnaxiously aggressive and unbearably judgemental, paintings and human race concerned, for which I was burned many times. Man, I am going hear no end of it if the piece comes back judged as Kiyomaro. Serves me right. Our teacher's efforts did little to change the percentages, but they did change the behavior. The passives 60% learned to openly join opinions of those few capable of having them and explaining why they support the said opinion even when called imbeciles by the superiors. 10% of industrious book memorizers (i.e. "the girls") would spend a lot of extra time building arguments around their readings. Exactly two people in the class learned to build arguments why the composition is weak here, the color is strong there, and the museum's curator is a random lazy bumpkin who could not be bothered to accent this through proper lighting. I shiver to imagine what the merry crowd would feel when instead of scary imposition "who decided its Kiyomaro and why", after half a year in the field they would be forced to participate not in cantare della gran belezza, but grand review of why we got so many of our own dispatched and how our decision making needs to be improved. Aufrichtig und Geradlinig... Not something one learns from drinking at DTI with random classes. In the past at least we could rely on occasional mass slaughter to keep the traditions alive.

I often look at threads like this one and wonder - why do the participants collect nihonto in the first place? If its driven by a genuine interest in nihonto specifically, why no one can substantiate an opinion? If its a social club where you cover for "your boys", it can be done frankly in every subject and every community. No need to study, travel, invest etc.. Think about the amount of time and money saved by shifting to politics. If its about being close to weapons, one expects at least some measure of valor to residually "rub off" the participants. There is obviously none: secret opinions to be revealed when they match the shinsa and no desire to defend what was stated publicly. Risk aversion taking to the extreme. What's exactly the point then?

there are three mainline smiths which are considered as individuals, the rest are sort of interchangeable and indistinguishable. The issue is the nakago and especially the second kanji, to the point of asking oneself is this gimei or real, and if real than its quite unusual and if one can find something similar. The writing is not typical, but its well done so there is a chance.

I did paper one. Kyu-gunto fit done in a rather brutal fashion. My feeling in Meiji period he was valued but not tremendously so. I had a nightmare selling it (and for peanuts basically) as every person on ebay felt his duty to tell me how awful it is to sell mumei shinshinto blades. On the other hand never heard of ubu mumei Kiyomaro. Attributions to him tend to hold (not green papers to nijimei). One of the strongest jigane makers in shinshinto with very bright itame and a distinctive hamon with nioi base which changes a lot with light direction and topped by nie clouds with rather large nie crystals.

I was told in the past that my judgements on Kiyomaro are shallow being based on but a handful of his iconic works and missing/ignorant of everything else. Tough truth. I can take therefore a bit of responsibility - since you and Ray feel strongly its a high chance Kiyomaro and almost certainly his school, a wager is appropriate. I'll be betting on it not having Kiyomaro, Den Kiyomaro, Kiyomaro Den in the attribution.