Oh okay! So for the ranks for the Gunzoku were a bit different than the regular imperial army. Excellent info! Always love learning more. Have a book or two coming in that really focuses on these times so I can brush up.
Definitely will get those pics in for you. Other than some minor rust it's in pretty good condition. No rot on the leather. Had to reglue the wood scabbard as it was seperating but overall it's a beauty.
When I first looked it over I checked for the usual stuff, faked patina, a number stamp in the wrong place, like on the habaki, ECT ect. But when I picked it up, felt the balance, looked over the geometry of the blade and even under the little rust the old polish still makes you pause. Hada present, nice grain, beautiful hamon.
After I'm back from my trip I'll give it the rust a little attention and see how it cleans up and then take some photos.
And don't worry for those of you likely gasped at any mention of cleaning/polishhing! I'll approach a "cleaning" the same way I do antique books or violins that have old metalwork decorations, gold leaf, etc etc.
Which, without going detail can be summed up simply as nothing abrasive, check your work constantly, take your time. And personally I like doing it on camera under microscope, but that's just my paranoia built up from violin restoration. (Keyword: ground. Never break the paper thing margin. Will drop a 50k to 5 bucks in two seconds!)
Now, question along these lines. I know generally bone is okay for slight rusts on most metals, even most softer metals. However some metals react negatively to certain animal bones. Does traditional Japanese steel have anything like that. Where it has a reaction to certain animal bones or hell, even proteins?
I couldn't find anything in particular other than antlers and bone tend to be acceptable in general. But I thought I'd ask while I have the attention of the experts here.