Hi,
Peter,
This blade is obligatorily gimei (except in the case of an unrecorded smith), It is shinto an there is no Yasumitsu in Osafune shinto School (mainly Sukesada). However, i think this gimei was done without a bad purpose; maybe a gift.
Hi,
Ni 二 is a sino-Japanese character. Futa(tsu) 貳 is a pure Japanese character, maybe some "chauvinism" in its use.
On the other hand it seems futatsu 貳 is more used in legal document.
Hi,
He is quoted in the Koto Nyumon (Iimura) and in the Toko Taikan (Tokuno). Only 900 man, far from a Sai-jo. The blade for selling by Aoi-art is the same than the one shown in both books.
Hi,
There are no Gassan smiths since late Koto (Tensho) until Shinshinto (Bunsei).
The hada discussed is not ayasugi and i don't think this blade is a Gassan one.
Hi,
FWIK, the hamon is the line separating the hira-ji and the yakiba, the nioi-guchi or habuchi (they are same things) is a integrative part of the hamon, its separates the hamon from the hira-ji.
Hi,
Advice is cheap....
Save your money, take time to store some knowledge (books are a good investment) try to see blades as much you can, and later when you will be able to make the difference between a good decent blade and a poor tired one, buy.
don't put the cart before the horse.
Hi,
Yes it is Shinto. Osaka Ishido smiths worked in Bizen ichimonji style. It is different from the Koto in its yakidashi and its boshi, there is also some running masame in the kitae. Osaka Ishido is one of the rare schools producing utsuri in Shinto times. Tatara Nagayuki was one of the most known