Iron Oxide added to Shudei

[S_B]

I have yet another question for the experienced seniors in this forum (my apologies for the many questions I've asked lately!)

Reading back through old TC posts, I stumbled across a claim that Yamada Sou adds iron oxide to his clay. I am curious if this is speculation based on color, or is something very obvious to the trained eye, or if it is mere hearsay that has not been corroborated. While I find his kyusu designs delightful, it would be a shame if iron oxide was added simply to create a deeper color!

I would love to hear more information on clay facts if anybody is at liberty or willing to share! Thank you again for all of the opportunities to learn!

[Bok]

From my own research I can add that the clay the Yamada clan has been using has changed with the generations due to scarcity and depletion of the original Tokoname red clay:

Jozan I-II used it still un blended. According to Hojo, Jozan III might have still used some in his early period, but then it had become too rare.

The Yamadas claim that their grandfather had put away enough to last for generations, but a simple visual and sensual examination reveals that clay has been changing from one generation to the next, getting redder and chalkier, not wet, satiny and orange like the early Tokoname clay. @Baisao correct me if I’m wrong here!

So, while I don’t know what exactly has been done to the original Shudei, it’s definitely not the same it used to be.

[Baisao]

I confirm what @Bok is saying is correct. There are obvious differences in the fired clays used across the generations. The shudei used by Jozan IV is now, at least the past two years, identical to what’s used by Sou Yamada. It has a chalky texture.

Sou has said that his grandfather collected enough shudei from around the [country or countryside] to last the family for generations. Presumably so they wouldn’t have to add things to it. Even if this is accurate, it’s not the shudei of his ancestors.

I’m hesitant to speculate on whether iron has been added but I will say that late Jozan III is redder than earlier, and it stays redder until recently when their clay has the chalky texture we’ve mentioned.

IMO the redder clay behaves about the same as the old orange clay but not the same as the new orange chalky clay. Neither is as different as mumyoi is from shudei.

HTH

[faj]

Neither is as different as mumyoi is from shudei.

Could you describe how mumyoi differs from shudei in your experience? Do you have a preference for one or a tendency to use each with different teas?

[S_B]

So, while I don’t know what exactly has been done to the original Shudei, it’s definitely not the same it used to be.

It seems well documented by users that the clay as far as color and texture as well as texture has changed quite a bit in Sou's hands. I am hoping still that whatever the changes are, Iron Oxide would not be the culprit for some of the changes! It seems strange to me (though not when thinking about my more familiar background with yixing pots) that Sou would claim his family had stores of clay built up just to say it...but if there is more motivation for him behind that with his reputation on the line, that would also be interesting to know more about

IMO the redder clay behaves about the same as the old orange clay but not the same as the new orange chalky clay. Neither is as different as mumyoi is from shudei.

To add to @faj's curiosity, I noticed that you have also mentioned your enjoyment of Mumyoi clay for your Japanese greens. I am curious if this is also reserved to vintage mumyoi, or if items such as those Hojo offers still fit the bill for Mumyoi clay. As always, it is a treat to hear more!

[Baisao]

@faj & @S_B

I have no experience with modern mumyoi or the artists Hojo works with. My experience is with vintage mumyoi and I would describe it as contributing a smooth texture to tea rather than the gently prickly texture of oxidation-fired shudei. If you are familiar with the black, reduction-fired shudei (I don't recall what it is called at the moment), mumyoi is a lot like that. I don't detect any differences in flavor, per se, but the texture of the tea is very different. I like shudei, mumyoi, and reduction-fired shudei depending upon my mood.

I don't think that Sou was misleading in his comment about his grandfather gathering clay. My guess is that they are working through a kind of clay that just happens to be different than the clay Emu and his father used. Alternative theories: 1) it could also be a stylistic choice to use the clay they are using now; 2) perhaps there was a firing problem in the samples that I have that resulted in the chalk-like texture; 3) perhaps the good clay is gone for shudei and is why much of Jozan IV's and Sou's work are glazed and reduction-fired.

Get one of each and see what you like.

[S_B]

I'm going to post these to add context from this thread on teachat, saying that there is "little doubt" that oxide is added...I would love to hear where this information had come form, as I am unable to find anything with my limited knowledge/connection/resources that corroborate this. Below are clips of the threat that make this claim:

* as a quick note, I don't know who these community members are, and this is by no means a callout, I'm just interested in learning more about the topic.

山田想氧化鐵1.PNG (219.16 KiB) Viewed 3320 times

山田想氧化鐵.PNG (219.69 KiB) Viewed 3320 times

[Baisao]

I'm going to post these to add context from this thread on teachat, saying that there is "little doubt" that oxide is added...I would love to hear where this information had come form, as I am unable to find anything with my limited knowledge/connection/resources that corroborate this. Below are clips of the threat that make this claim:

* as a quick note, I don't know who these community members are, and this is by no means a callout, I'm just interested in learning more about the topic.

Just to put my stance out there regarding iron oxide in shudei: I don’t care either way, except to have more knowledge.

Let’s ask the source:

@Tead Off - how do you know for certain that Sou adds iron oxide? Some people here are curious about your statement on Tea Chat. Cheers!