Interesting utsuri

[Jim P]

Hi guys, Aoi Art list this as utsuri, I was wondering if someone knows how utsuri that covers the blade like this (http://www.aoijapan.com/kakatana-suishinsi-masatsugu) is done? it almost looks like Hitatsura.

[John A Stuart]

Strange in that it is described as mujihada then uzumakihada which is produced in swords with a coarse mokume/masame hada. Anyhow a proper ustsuri? It seems more an effect within the steel apart from the hamon although a result of yakiire more like hitatsura as you suggest to me as well. John

[Jacques]

HI,

 

Maybe i'm wrong but i would have named it namazu hada instead utsuri.

[paulb]

This is strange, I cant remember seeing anything so vivid before. It re-opens the ongoing debate about what utsuri is. Probably an over simplistic view but I tend to think of descriptions of hada or jigane as relating to the composition of the raw material used and the way it is forged. Although utsuri is effected by material used I tend to think of it as a creation of the quenching process. therefore describing what is seen here in terms of hada as well as calling it utsuri is a little confusing.

From what I can see on the image posted I dont think this looks like a function of the hada it appears to be very extreme and vivd utsuri (strong antei as well) The nearest description I would think of is jifu but as suggested above it is very extreme and lacks the subtle beauty seen in the jifu of older work.

very dramatic but for me not particularly attractive.

[cabowen]

Utsuri is indeed produced by quenching/tempering, which produces martensite, pearlite, bainite, trootsite, etc.forms of carbon in the iron matrix. Utsuri is composed of these microconstituents of the steel that occur during the transformation of austenite. Due to hardness variations, it appears after polishing.

 

It occurs naturally due to the cooling gradient. All the variables have to be "just right" for it to form. Sometimes, like in koto Bizen, due to the smiths uncanny ability to consistently reproduce these conditions, it is quite common. Sometimes though, as is probably the case with this blade, it is simply a rather random occurrence which, due to the cooling gradient, the distribution of carbon in the blade, etc., is quite uncontrolled....

[Jim P]

Hi guys, Paul I also can not remember seeing anything so vivid before and it looks like like hitatsura so it has me scratching my head its description as glowing utsuri is the first one I have seen.

Chris, you think its a random occurrence I wonder ? it does blur the line.

Jacques, Namazu-hada means a spotted appearance that made of two different colored steels. as in the Aoe school eg, http://www.ksky.ne.jp/~sumie99/Aoe.html don't know if it apply s if it did we would have seen more like this ?

[cabowen]

Hi guys, Paul I also can not remember seeing anything so vivid before and it looks like like hitatsura so it has me scratching my head its description as glowing utsuri is the first one I have seen.

Chris, you think its a random occurrence I wonder ? it does blur the line.

Jacques, Namazu-hada means a spotted appearance that made of two different colored steels. as in the Aoe school eg, http://www.ksky.ne.jp/~sumie99/Aoe.html don't know if it apply s if it did we would have seen more like this ?

 

To answer the random question for yourself, have a look at the work of Suishinshi Masatsugu and see how many of his blades have this feature.

 

As a member of the Suishinshi group, he was undoubtedly trying to recreate the koto techniques. Here, he succeeded in producing utsuri, but in a rather clumsy and amateur way.

 

If you think of utsuri as steel that is not quite as hard as the yakiba, but harder than the ji, it is, in a way, a soft hitatsura. In other words, if the cooling rate would have been a bit faster, he would have ended up with hitatsura instead of utsuri...

[Jim P]

Thanks Chris, it does make it a bit more clear (a soft hitatsura) sounds good. In photos its hard to distinguish between the two, must be different in hand.