One of my favorite pots

[Brian Van Fleet]

Thanks, Brian! It's been a long time coming, but I'm finally in! The first one is my favorite as well... the prototypical Tofukuji glaze that we all covet. I will say, though, that the second one is really very nice, too... a much more subtle glaze for a Tofu, but clearly his work, and the dimensions of the pot make it much more usable. Now, to find a tree that deserves to be in it...

No doubt! It even has a little red from reduction. Kinda adds a unique element.
I like the bottom of the second one better than the sides, and it’s a usable size.

 

[Deleted member 21616]

It even has a little red from reduction

Brian is that what happened to this koyo? I think Ryan’s page on Koyo says something like ‘when oribe develops red, its the side facing the fire?’ But this pot has red on all 4 sides

Reduction is lack of oxygen, whether its deliberate or accidental?

 

[Brian Van Fleet]

Brian is that what happened to this koyo? I think Ryan’s page on Koyo says something like ‘when oribe develops red, its the side facing the fire?’ But this pot has red on all 4 sides

Reduction is lack of oxygen, whether its deliberate or accidental?

Others are probably more qualified than me to answer this question. But my limited understanding is that copper glazes are green when fired to a certain temperature (cone 6 maybe?), and turn red when fired higher, and/or through the reduction process. It would stand to reason that direct contact with fire would make that glaze hotter (and have less oxygen) than the other side, resulting in the red look.

I think that a subtler effect is the milky blue look you see in some of the copper glazes, and it makes me wonder if those spots would be red if left a bit longer:

 

[Deleted member 21616]

@Brian Van Fleet that makes sense thanks so much!

That explains how Koyo's green oribe pots get those blue patches! Until now I thought it was done with a splash of a different glaze, but now that you mention it it's obviously just done with heat, even when the blue seems to be intentionally placed as when they commonly do the 'tofukuji stripe' (pic attached). Thank you!!

so with increases in temperature and/or time, green>blue>red

I spoke with Koyo and they apparently can no longer produce blue oribe, but Green oribe is no problem (see attached)

It makes me wonder whether this koyo on ebay is a 'true' blue oribe pot, or if it was a green oribe pot left in too long/hot that turned blue? (pic attached). if so, guess who really wants to see a blue-red or full red oribe!!!

This sounds like another puzzle for @Roy Minarai

https://www.ebay.com/itm/Tokoname-H...rentrq:102f743b1690ac3c3bb57debfffbfe87|iid:1

Brian is that Koyo (maybe Ino?) in the second pic yours? love it!

 

[Brian Van Fleet]

Brian is that Koyo (maybe Ino?) in the second pic yours? love it![/QUOTE]
Yes, it’s mine, and it’s an Ino. The proportions are so nice, it could be almost any size, but it’s about 4.5” wide.

 

[Deleted member 21616]

The proportions are so nice, it could be almost any size, but it’s about 4.5” wide.

perfection!

 

[Roy Minarai]

Others are probably more qualified than me to answer this question. But my limited understanding is that copper glazes are green when fired to a certain temperature (cone 6 maybe?), and turn red when fired higher, and/or through the reduction process. It would stand to reason that direct contact with fire would make that glaze hotter (and have less oxygen) than the other side, resulting in the red look.
View attachment 228375
I think that a subtler effect is the milky blue look you see in some of the copper glazes, and it makes me wonder if those spots would be red if left a bit longer:
View attachment 228374

No that’s not the case - temp doesn’t control copper color. Amount of oxygen available in the kiln atmosphere does, the introduction of tin oxide can also turn copper glazes red in oxidized firings, but not the same reds that typically we see on bonsai pots like the half red half green pot pictured above. When the kiln is fired in a reduced oxygen atmosphere copper becomes unstable and release very fine metal copper particles that pool and create the red color. In oxidized firings these particles are not released and the glaze stays green. Pots that are partly green partly red, were fired in reduction (albeit not full reduction) yet there was oxygen available at the surface of part of the pot and not the other. The introduction of silicon carbide to a copper glaze can create localized reduction as it will canabalize any available oxygen in the glaze and create reduction colored copper red in an oxidized firing, however, it is hard to get perfect and usually doesn’t look as true red as reduction reds. I would guess the blues in koyo pots are from barium or titanium in the glaze. Roy

 

[Deleted member 21616]

Thank you so so much @Roy Minarai

this is all so interesting!!

 

[Deleted member 21616]

Nelson pulls through again!

a while ago i put him on the hunt for a yellow shallow oval, and for any good example of koyo's yellow crackle -- he found one 22" pot that killed two birds with one stone!

he also found this 18" shallow blue oval with some great patina from its time at fuyo-en! shallow blue ovals have a special place in my deshojo filled heart

 

[Dav4]

Another nice pick up for me that will hopefully have a nice little Japanese Blackpine in it in a year or two… Gyouzan.

 

[LanceMac10]

I'd appreciate it if you folks would stop buying all my pots!!!!

My goodness, some nice stuff!!!

 

[-norwegian_blue-]

Another nice pick up for me that will hopefully have a nice little Japanese Blackpine in it in a year or two… Gyouzan.

Is that one from my buddy Joe? nice pot.

 

[Dav4]

Is that one from my buddy Joe? nice pot.

Yup... and I thought I had it bad!

 

[Brian Van Fleet]

Another nice pick up for me that will hopefully have a nice little Japanese Blackpine in it in a year or two… Gyouzan.
View attachment 229644View attachment 229645

Nice buy. I was tempted by this one too. Bought a persimmon instead.?...which is gonna need a pot eventually.

 

[Deleted member 21616]

two interesting ones might be worth sharing ?

i posted the first pot earlier in this thread (post #702) in a discussion about green/red glaze. The pics were from matt

this is a pot matt sourced for me during his 2 recent trips to japan. I had asked him to keep an eye out for old/weird koyos.

it just showed up today, and it has this crazy lightning effect?? Reminds me of the holographic pokemon cards i used to play with as a kid!

for some reason this didn’t come thru on any of the pics matt sent! very nice surprise! The lighting actually shines on the whole of one side of the pot at once in the right angle, but it’s impossible to photograph more than a section of it



second one is an Aiba Bunkichi. So most people know Aiba Kouichirou (Koyo) and Aiba Kuniaki (Kouichirou’s son, Juko). Aiba Bunkichi is Aiba Kouichirou’s father. Primarily a tile maker, he made a few pots here and there (confirmed by MRB and Koyo directly)

 

[Tentakelaertje]

two interesting ones might be worth sharing ?

i posted the first pot earlier in this thread (post #702) in a discussion about green/red glaze. The pics were from matt

this is a pot matt sourced for me during his 2 recent trips to japan. I had asked him to keep an eye out for old/weird koyos.

it just showed up today, and it has this crazy lightning effect?? Reminds me of the holographic pokemon cards i used to play with as a kid!

for some reason this didn’t come thru on any of the pics matt sent! very nice surprise! The lighting actually shines on the whole of one side of the pot at once in the right angle, but it’s impossible to photograph more than a section of it

View attachment 230570View attachment 230571

second one is an Aiba Bunkichi. So most people know Aiba Kouichirou (Koyo) and Aiba Kuniaki (Kouichirou’s son, Juko). Aiba Bunkichi is Aiba Kouichirou’s father. Primarily a tile maker, he made a few pots here and there (confirmed by MRB and Koyo directly)

View attachment 230580
View attachment 230581

Wow the story behind that Bunkichi one is awesome! Congratz on fetching those!

 

[Deleted member 21616]

Wow the story behind that Bunkichi one is awesome!

I’ve been nerding out on koyo’s history.

Believe it or not, until i showed them proof from Koyo-toen, Tokoname headquarters had no idea that Aiba Bunkichi ever made a bonsai pot! They thought he only made tiles etc.

the subtleties in the signature and craftsmanship are unconceivably minimal. Very very hard to spot a bunkichi vs kouichirou, so i learned recently from MRB and Koyo! I still wouldn’t be able to distinguish them reliably myself even if i had one in my hands! I can’t even say that i’m going to keep an eye out for them, i’d be fooling myself

 

[Gsquared]

One of my favorites. 14” across.

 

[PiñonJ]

Took some quick snaps today with my iPhone to try out my new photo lights.
Brand new Sarah Rayner:

 

[PiñonJ]

Horst Heinzlreiter: