Kanayama(?) Tsuba #1

[JohnTo]

The first tsuba that I am presenting for discussion was bought at a general art auction in which several lots of tsuba appeared, probably from a ‘deceased estate’.  Foolishly I did not bid on this one as I thought that it might go for big money and I was saving for another auction.  It was unsold and came up again at the next auction and I was forced to pay over 4x the same low estimate.  Damn!  The tsuba came in an old collector’s box and was obviously a cherished pieced.  I became interested in this tsuba via a photo on the internet, despite observing that the tsuba had been modified (see below) and I fell in love with it when it arrived in the post.  The tsuba is in good overall condition with no rust scabs.  There were a few spots of red surface rust in the crevices, but I removed these with the aid of a WD-40 spray, dental flossing brush and kitchen tissue, followed by drying on a radiator to remove traces of WD-40.  I rather like WD-40, a fish oil based product, as it is designed to get behind rust and disperse water.  I’m not a give it ‘a good rub with a piece of horn man’. If it don’t come off with a brush, I leave it.  But then I don’t buy seriously rusted pieces.  Anyone like to comment of my cleaning method?

The tsuba is a simple round iron sukashi (Height: 7.95 cm, Width: 7.85 cm, Thickness: 0.45 cm centre, 0.4 cm rim) with a dark, almost black, patina and two kogai hitsu ana.  The nagako ana has a small copper sekigane at the narrow end and just two small punch marks either side at the bottom.  Evidently this tsuba has not been mounted on numerous swords.  The design, as it is now, is a simple curved square or star, slightly out of true, having small curvature in the north-south axis.  Quite zen like in its simplicity.  I have seen this design referred to as a (silk) bobbin, but I don’t think so, bobbins are just simple wood crosses and why would a samurai choose to display a woman’s weaving implement? I’ve searched Japanese spinning wheels, but they are not like this shape.  It may be a mon, a variation on the straight sided diamond shape often seen.  I’m going to call it a star.  Any suggestions?

However the design was not always this simple.  Look carefully and you will see the stubs of pairs of bars in each of the four piercings on both the rim and central star.  As far as I can see these ‘bars’ were cut off with a chisel sometime in antiquity.  Perhaps it was even the tsubako, or initial vendor who did not like the design and removed them.  The surface of the stubs looks smooth compared to the edges of the sukashi design, so I guess the bars were cut off sometime after manufacture then repatinated.  Perhaps the kogai ana were also added at this time.  Normally, I would not be happy to find that a tsuba had been modified from its original design, but in this case I feel that it has been enhanced.  I even love the stubs of the bars, which could have easily been filed down and left no trace.  They show the history.  To my eye, this tsuba is like a zen monk who has achieved enlightenment and has emptied his mind of all extraneous thoughts.  I really love this tsuba; designs do not come any simpler.  Any comments about the original design and modifications?

The delicate nature of the rim seems to shout Kyo-sukashi, or possibly Owari, but I’m going for Kanayama (which some authorities say was situated in Nagoya, Owari province anyway).  The main reasons are the irregular surface of the outer rim and the simplicity of the sukashi.  I have seen Kanayama tsuba described as having ‘exploding tekkotsu’ due to trapped carbon exploding in the final forging process.  Personally, I’m not happy with the ‘exploding carbon’ explanation, if carbon exploded when heated, the tsubako’s forge would go up, being filled with carbon (charcoal)!  It could well be that the rim was exposed to excessive heating during a final heat treatment.  I did a one day blacksmith course a couple of years ago and made a couple of fire irons.  I overheated one piece during the final tempering and burnt similar pits in the steel (see pic).  The fire iron was made from a piece of mild steel, but the surface is similar to some tsuba that I have seen for sale described as having tekkotsu, which my fire iron obviously doesn’t have. This made me wonder if this tsuba was covered in clay for the final temper, like swords, leaving a thin coating around the sides to make the iron harder, but exposing the rim to burning, like my fire iron.  Alternatively, the central part of the tsuba could have been covered with sand to protect it from burning and heated on a spatula before quenching.  Hardening the rim and leaving the centre a softer iron makes sense to me, especially if the seppa dai is going to be subjected to a good old bashing to change the shape of the nakako ana.  Sasano quotes sources that say the open nature of Kanayama tsuba means that they are no good for defensive fighting, as so much metal has been removed.  Hardening the outer rim would counteract this limitation.   

I have long been interested in forging iron, perhaps it is because my father and grandfather were blacksmiths in the UK.  I never had the chance to see them at work, but I guess they left iron in my blood.  I have seen Ford’s excellent videos on making soft metal tsuba, but have been unable to videos showing iron tsuba being forged.  Anyone seen one?  Talking to a couple of local blacksmiths has given me a different perspective on forging.  Use of template tools, to make life easier, is one.  The kogai ana appear to be are identical and have a minute raised rim around the outside (see pic).  I reckon that a shaped punch (blacksmiths call it a drift) was used to finally shape the openings and the iron pushed up around the edges trimmed off.  The main sukashi shows a difference between the edges of the central star and the rim.  The inner edges of the rim seem to be quite flat, whereas the cut edges around the central star seem convex or layered.  Akasaka tsuba are known for their three layered sandwich construction, with a soft iron core, but I can see no evidence of joins.  Could it be that the tsubako cut the sukashi design from a soft annealed iron plate (to make cutting easier) and then hardened the surface of the iron in the final yakite.  If only the outside of the tsuba became hardened (martensite), the higher density soft inner core (austenite) would shrink relative to the hard steel, as in Japanese sword making where the soft back of the sword results in a straight sword becoming curved after the final quench.  This might explain why the cut surface of the star became convex, while the rim (all martensite) remained straight.   

Tekkotsu on this tsuba? I don’t think so, but I’ll leave you to judge.  I have a tosho tsuba with tekkotsu, about 2mm by 1 mm, popping out of the iron like dinosaur bones from a rock face.  These, if tekkotsu, are small, but I’ve seen tsuba for sale with similar irregularities described as tekkotsu (everyone seems to love a pile of old bones).  What I also like about this tsuba are tiny bright specks scattered about the surface, in the central part, inner and outer rim.  I think these are fragments of hard iron (martensite), less than 1 mm in size, which have either failed to take up the patina, or have had it rubbed off over the years.  I’ve never seen this before, but I suppose they could be considered as small tekkotsu.  I think I have managed to capture the feature in the attached photos.  Some are bright and look like iron, but some look like tiny grains of sand imbedded in the iron.  The Nihon To Koza, VI, p50 states that ‘speckles’ are common in Kanayama tsuba due to the yakite finish and these specks could easily be described as such.  Kanayama tsuba tend to be small and often have heavy rims, but I gather that early ones often have quite delicate and fancy rims, so I’m reasonably happy with my assignment.  But please feel free to challenge and comment on any of my observations.

Best regards, John

(just a guy making observations, asking questions, trying to learn)

Photos: #33 Tsuba side 1

#35 Tsuba side 2

#37 Pitted (burnt?) rim

#38 stubs of bars, speckle (to right) and concave surface of edge

#80 speckle below nagako ana

#89 Edge of kogai ana, showing narrow rim, indicating that a drift was used to shape the opening.  Can you also spot the speckles?

#61 my fire iron showing burnt steel and tekkotsu (not really)

[seattle1]

Hello JohnTo:

Thanks for your very interesting and well written text. I don't think I have seen that kind of careful deconstruction done here before, and I hope we will see others venture as you have done.

I suppose the tsuba might be Kanayama, the thickness is there and were the pieces supposedly there once still in place, more robustness, a Kanayama characteristic, would be there, though it has more of a Kyo sukashi feeling to me.

In any event, nice job!

Arnold