SteveM

I don't think the kissaki was reshaped. I think its the original kanmuri-otoshi style. The origami doesn't mention any reshaping of the kissaki. In the section under the heading "nakago", it notes that the butt-end of the tang was cut off and is now "kuri-jiri" style. I don't think this sword would be designated Juyo if the kissaki were altered. It is still called "ubu" because the machi have not been significantly altered. I'd just note to Nathaniel not to expect consistency in sword or tosogu terminology, especially with these earlier papers. It's maddening, but one learns to live these oddities.

Resident of Nagoya in Owari province. Late Edo period. (per Wakayama). Same school as Shigemasa and Shigemitsu (重正 and 重光, respectively). Very short entry.

Small correction: Jakushi = 若芝

Should be the signature of Tadatsuna (忠綱). On the reverse side is the date: Showa 18, December (1943). (posted almost simultaneously with Moriyama-san above) More info below

To me it looks like Ishikawa Suishinsen, but there is something after that which I can't make out.

Hello Bryce, thank you very much for that. Now I'm even more intrigued. As I mentioned, the two vertical lines on the far left of the bag indicate what is written on the mei. Or, that would be the normal interpretation of the words prefacing those two lines; 銘曰 (mei iwaku)(picture below)*. Your translator has translated this word as "Iron speaks" which is a mistranslation. It literally means "The mei says...". The problem is, those following two vertical lines on the bag are completely different from the mei on the sword. The lines on the bag read, as I mentioned, like Chinese couplets or quatrains or something, but they have nothing to do with the mei, from what I can tell. So, other than the first line (This sword, a Gassan Sadakazu work, is a family treasure), and the date, the rest of the writing is rather enigmatic. I can see how your translator arrived at some of the phrases, but for me it seems a bit too florid. It feels a little off to me, but maybe the writer was trying to be poetic. A couple of the connecting words and phrases are slightly hidden by folds in the cloth, so maybe a clearer shot would help make the preceding part make more sense (to me, anyway). *I just wrote about this phrase in another thread, where I mentioned that it was a phrase only used by Kazutaro Torigoye. It's appearance here is a very interesting coincidence.

Would it be possible to flatten out the cloth so that the characters are a bit more readable? And, could you give us a shot of the tang? The last two lines of the cloth are just repeating what is written on the tang of the sword (supposedly) so I'm curious to see the tang. From looking at the cloth, it feels like the writing on the tang is some kind of classical Chinese poem or something. It doesn't read like typical Japanese language of the early 20th century.

トキワ　Tokiwa - it is a location in Tokyo (Tokiwamatsu-chō) where Shigetsugu's forge was. Near present-day Shibuya. https://ja.wikipedia.org/wiki/常磐松町

Not water dragon, but "water tiger". December 1842 is as close as you'll get. No specific day is mentioned. December is a translation used for convenience. I don't know the precise start/end dates of the Twelfth Month for 1842. I would use "published" rather than "printed". I somewhat minor difference.

銘□ →　銘曰　never sure how to read this, but most often written in English as mei iwaku. I think only seen on Torigoye boxes.

Poem by the Chinese poet Xie Zhen (谢榛). Hopefully one of our Chinese-speakers can provide an English translation. 花神默默殿春残，京洛名家识面难。国色从来有人妒，莫教红袖倚阑干 https://en.wikipedia...wiki/Xie_Zhen_(poet)

義完 (Yoshisada) is a possibility. This thread mentions Ishihara Yoshisada signed his name two ways 義定 and 義完 (both read as Yoshisada). I haven't found any corroborating evidence for this, however.

Looks like 勝 (Katsu) on the left. It is a mildly unusual family name, but not a one-of-a-kind family name, so Katsu as a surname name is one possibility.

すっきり Thank you Markus. (And well done, Uwe for picking out 披...my mind wouldn't accept 披 or 波 etc... I had the aperture set too small. Need to always look at the bigger picture)

Possible, but I was swayed by the ume branches of the design, and that preconception keeps me from imagining anything else (even if I admit that it doesn't look too much like the cursive form of 梅).

弘寿（花押） Hirotoshi

Can't get it. Maybe someone can correct/guide. The side with the cloisonné should be the omote/recto, and the plain side is the verso. 梅囗囗屋之 にしき登々乃い

Made with Yasuki steel （以安来鋼). 　 Imperial date of 2601 (1941).

Smallish corrections 紺系縅具足右袖　　right sleeve of navy odoshi gusoku 長さ 二尺二寸七分　2 shaku, 2 sun, 7 bu 室町時代の将軍格のものと思われる. 具足の右袖で特に貴重な文化財として筑後国住武藤家に古くから 伝来した名品也 明治参拾貳年春 武藤秀弘 The paper with the kamon says its from the collection of the Takahara family, and the mon is a fan (hi-ōgi) with a tortoise shell (hexagon) border.

Possible to get a picture of the whole tsuba to see how the writing is oriented? Are these lines all on one side, or are they on different sides (recto/verso) of the tsuba?

Yes, that is correct. According to Aoi, this Tomoyasu is the son of Tomonari (友成), who is supposed to have been the origin of the Ko Bizen school (c. 987). Which would place his son (Tomoyasu) around the 1000s (Kanko era, as indicated on the sayagaki). But this leads us down a little rabbit hole, as there is a divergence of opinion about Tomonari. Anyway, without getting into those details, I can only repeat what Jussi says; a blade that appears to be from the early 1000s, that has a plausible signature from Tomoyasu, would be interesting from a historical perspective even if it were retempered. A real unicorn.

I'm curious about the sayagaki. Anybody know anything about the writer, Sekizan? Looks similar to Satō Kanzan's writing.

I'm not sure because the resolution makes it a bit grainy, but I think one side is the forging of the sword in August of 1851 by Eiji, son of Gomura, and the other side is the quenching of the sword in February 1852 by Hideyoshi, son of GoXX (doesn't look like Gomura). Anyway, a gassaku. The August and Feb dates are probably just the normal, "traditional" good luck inscription dates.

*The translator has entered the chat* My gut feeling is that the "to mei ga aru" in this case refers to the Koson signature, and not the Nobufusa attribution. The NBTHK attributed the sword it to Nobufusa, so the "to mei ga aru" only makes sense if it refers to the Koson signature. (Meaning: they doubt Koson wrote the shumei. Or, I should say, they have no consensus about whether or not the Koson shumei is authentic). But, I say this without having consulted with either Tanobe or the NBTHK, and it is just a gut feeling.

Often those sites will provide a list of noteworthy families who used a particular crest, but the site I linked to doesn't list any such families, so its a bit of a dead end. But as a side note, family crests were used by multiple families, so its often difficult/impossible to pinpoint a crest on a sword to any one family.