Need more mei help, and some tips on removing copper corrosion

[GRC]

Sorry to double dip in topic heading because it's two totally different topics, but I need help with both.

I tried to figure out the mei on this kinko piece, but had no luck at all.

Here's it is: a kawari fist shaped tsuba, entirely soft metal, copper base with a bronzy-black finish (shakudo maybe?), it has a karakusa design on the front with the Takeda family mon, while the back has general texturing along with a moon, boat, waves and wind incorporated in the design: These two images are really oversaturated with light just to make the mei as clear as possible.

It originally had more green corrosion on it (see below), but I gently rubbed a lot of it away with mild soap and water.

Does anyone have any suggestions, other than to keep at it with the gentle soap treatment?

Thanks!

 

[kyushukairu]

The mei looks like ‘Yasufusa’ (安房). I had a quick look in the meikan and it seems there was a smith by that name who was a student of Yasuchika. However, as can be seen in the attached image, the style of the kanji is slightly different and there is no kao to compare. 

With regards to the oxidisation, I have had a low-grade shakudo tsuba with some light patina issues like that in the past and the application of choji oil cleared it away. However, you may want to seek the advice of those with a background in metalwork before using choji, just in case it has any detrimental effects upon the integrity of the metal. 

[GRC]

Thanks Kyle!!!

That reading of Yasufusa helps a lot.

I just checked Sesko's Genealogies of Japanese Tsuba Artists, and there's a Yasufusa listed as 4th gen of the Awa Shoami (aka Hirata school). If I extrapolate from the dates that are there, I'm guessing late 1600s, early 1700s, because the 6th gen is listed as 1721-1762. 

                                           

 

The seller also referenced "Awa" province, but I didn't make the connection until now.

And apparently the 1st-4th generations worked primarily in soft metals like "shinchu plate" (copper with zinc = brass I think), whereas 5th gen and onwards used mostly iron plate.

 

Actually, here's a whole past post about Awa Shoami on NMB from 2014:

 

[Ford Hallam]

To be blunt, this tsuba bothers me.

 

I would suggest disregarding the mei for starters as it really bear no similarity to the meikan examples and doesn't really even look all that confident on its own terms.

 

The kara-kusa pattern appears to be etched as does the reverse and while we do see etched designs in some work, Jakushi and a few Higo pieces...it's not really that common. My general impression is that this is a work by an amateur, quite possibly modern.

 

As to oil on verdigris, well it wont remove or eliminate it at all. It may conceal it by making the green less visible as it is soaked by the oil but the corrosion continues. In fact as oil is essentially a fatty acid this in combination with the copper present acting as a catalyst the corrosive effect is accelerated, resulting in a product conservators call copper soaps. Incidentally, Ibota wax, when it inevitably breaks down, causes the same problems. So I'd suggest not oiling soft metal, or even iron for that matter.

 

 

[GRC]

Thanks for the information about not using oil with soft metal. If that is to be avoided, can you suggest an alternate remedy for the verdigris, or at least something to stop its progression?

 

I can definitely see the etching method being used for the pattern on the front and back.

The moon is definitely inlayed because it is made of a different metal. It looks like silver, now that I have cleaned it some more.

I would also guess that the three mon were either carved or inlayed because of their sharper outlines and height above the rest of the design.

 

I quite like many of the etched tsuba designs that I have seen, although all the examples I have seen were in iron, not soft metal. An etched design definitely gives off a more "painterly" effect to the design, given that whatever "resist" had to be applied (by brush I assume?) onto the plate before etching. It's precisely the "unusualness" and "painterly quality" of this piece that caught my attention to begin with. 

 

As artisans, wouldn't many tsubako have experimented with etching at some point in their careers? Exploring different methods and techniques to see what they could produce with it.

 

Amateur or not, there's still a hell of a lot of work that went into this piece, and I'm happy to have it.

 

 

    

[GRC]

On the topic of etching, here's a few images for some eye candy:

The first two are etched for sure, but I'm not certain about the last two.

 

Here's a nice etched kinko piece from Richard George's (RKG) collection. Accidentally stumbled across it in the ancient "udenuki-ana" thread (which is an interesting read).

 

 

And here's a mumei iron one that was on YahooJ not long ago:

 

 

And here's two other ones that I suspect might be etched, possibly etched then chiseled, but not 100% certain... 1st is mumei, 2nd is a Jakushi (ura side).

 

[GRC]

Here's some more etched tsuba rom Richard's (RKG) collection:

Thanks for sharing!

If anyone else has some etched examples, feel free to post em  

 

 

[GRC]

and found some more etched tsuba in the Met gallery...

This one also has some inlays on the omote and is 16th century according to the Met:

looks like some kind of water wheel and stream on the back... hard to make out the details.

And another one... horses and a willow tree

and one more... this one has very cleanly executed etching 

[Iekatsu]

Glen,

The first example in your last post is actually a Kagamishi Tsuba, its cast bronze, not etched.

[ROKUJURO]

On 11/6/2021 at 12:55 AM, Ford Hallam said:

....Incidentally, Ibota wax, when it inevitably breaks down, causes the same problems. ....

Ford,

I have no personal experience with IBOTA wax, so I cannot comment on effects you have probably seen in hand. But these natural waxes usually do not contain fatty acids, they are mostly composed of wax alcohols.

Another general question are the protective properties of waxes. I did not know they were used as TSUBA care. Unless you melt them and immerse a TSUBA to cover it completely with a relatively thick layer of wax, there is no safety against oxygen attack. I don't think anyone would like that.

Rubbing wax on a surface usually does not produce an air-tight layer of material, I am sure.  

[Curran]

 

I sold this tsuba to Jean long ago. When it came back on the market, I tried to buy it. Someone got to it quicker.

Nice Hizen example of etching.

 

   *Hint*  current owner, if you are on NMB---   PM me.

 

 

[Geraint]

Here's one

.

 

 

Posted it some while ago.

 

All the best.

 

[GRC]

Thanks for the posts people! I was starting to think I was just talking to myself lol.

 

Iekatsu: is kagamishi a “mirror maker’s tsuba”? My search criteria was just to look for “soft”, “un-crisp” outlines on the relief patterns in the Met collection, then just relied on the technique description provided by the Met. But thanks for clarifying! There’s quite a few errors in tsuba descriptions in museums. I really wish they’d all put some more effort into cleaning all that up. But then again, most museums won’t spend the money researching objects that are mostly “not on display”. Such a shame...

 

Curran: that is a stunning wangata. I see why you want it back

 

Geraint: that looks like an interesting mix of carved and etched. Nice piece!

 

As for using oil on the copper based tsuba, I have to admit, I tried a bit of pure mineral oil on my tsuba before Ford posted his explanation of why you shouldn’t.

It did appear to make the verdigris (green corrosion) almost entirely “disappear”.

but then after reading Ford’s post, I washed it all off with dilute, mild soap, and voila, some of the green reappeared.

So the oil just disguises the corrosion, just as Ford explained.

So what really did most of the removal of corrosion, was me physically pushing it off with a soft toothbrush and a wood toothpick to get into some of the crevices and the thicker, more stubborn, areas of corrosion.

That whole experience served as a nice accidental experiment. I hope that helps some other members too.

Thanks again to Ford’s input on the matter.

[ROKUJURO]

Glen,

mineral oil (= derivates of rock oil/crude petroleum) does not contain fatty acids, so it will not cause the verdigris problem, but it will not remove it either.

[Kurikata]

Etched tsuba....from my collection.

[Ford Hallam]

Jean, with regard to Ibota wax specifically

 

"...ibota wax has a distinctive chromatographic profile containing a series of long-chain fatty acids with even numbers of carbon atoms, the most abundant being hexacosanoic acid "

Václav Pitthard, Sabine Stanek, Martina Griesser, Christiane Jordan, Silvia Miklin-Kniefacz & Richard Miklin (2016) The technical investigation of an eighteenth-century Chinese imperial carved lacquer screen and its role in developing an appropriate conservation treatment, Studies in Conservation, 61:sup3, 97-108, DOI: 10.1080/00393630.2016.1227117

[Ford Hallam]

I hesitate to write the following but I trust the sensible and considered approach most of the members here have towards their treasure in their care so...

 

A relatively safe DIY option you could use sodium bicarbonate, or even baking powder.

It's mildly alkaline and very mildly abrasive, very mildly, but it does actually have the ability to dissolve some corrosion products.

The only caution I would offer is that it not be left on the patinated surface for longer than a couple of seconds as it will break down the patina and make it dull and eventually begin to really stain it.

I'd suggest using a tiny amount (literally a few grains) on the tip of a damp toothpick. Rub only the actual corrosion and rinse under warm running water often.

 

Once you reach a stage you're happy with or wish to stop at rinse very well with soapy water, pat dry and warm with a hairdryer until just too hot to handle comfortably.

Have tissue on hand to blot up any water that may bubble out from under inlays. When completely free of moisture apply a little renaissance wax sparingly and gently buff to a soft glow as it cools. It's tough to get a good gloss on cold  renaissance wax.

 

Having offered this remedy I should also point out that sometimes certain problems are best left well alone, let sleeping dogs lie and all that. For example, I know of a fabulous fuchi kashira set of shishi by a big name Yokoya master that has a couple of tiny green, almost malachite like, beads of verdigris on the shibuichi of the shishi's body. These are impossible to fake and are evidence of decent age, they are not terribly ugly and removing them will leave a pink spot instead. So they remain and are appreciated as part of the overall piece and are part of its context.

[ROKUJURO]

1 hour ago, Ford Hallam said:

"...ibota wax has a distinctive chromatographic profile containing a series of long-chain fatty acids with even numbers of carbon atoms, the most abundant being hexacosanoic acid "....

Thank you Ford,

I did not know that (as so much more)!

[GRC]

Thanks for that Ford! 

I, and probably many other members of NMB, are immensely appreciative of that information. 

 

Solid reference BTW 

4 hours ago, Ford Hallam said:

The technical investigation of an eighteenth-century Chinese imperial carved lacquer screen and its role in developing an appropriate conservation treatment, Studies in Conservation

 Adds an new level of appreciation for your depth of study in this craft.

[Ford Hallam]

Cheers Glen

 

perhaps I should post some images of my reference library, the books on ancient iron and steel, and rust, alone would make the iron tsuba chaps weak at the knees