I’m lucky in that I can walk out my door and head up the hill for a walk, and I rarely encounter anyone else.
Today, I was passed by one car and was otherwise completely alone. It was a beautiful spring day after a day of rain and the mountain was lush. Several times on my way up I could smell the wild boars that must have been lurking nearby quietly. I don’t worry about them. The only time I ever see one is when they jump up to run away when I get too close on the road.
The road is roped off now, because of a landslide that damaged the road higher up, but it’s no problem for walkers to go through.
The hill slid out from under, taking half the road with it.Another area where a slide has taken down some trees.
Some other sights from the walk. The view from the mountain, some thistles at the side of the road, a slide which has exposed some clay, and a cantankerous snake.
A very nice walk, and a nice clay discovery, I’ll be heading up again from the other side in my car to get some for pots and glaze.
This last firing of the gas kiln I used draw rings to get a better idea of when certain glazes matured. I’ve known this for a while, but was struck again at how colorless and boring the colors of the glaze and clay were when yanked and doused in a bucket of water. So colorless, in fact, that two different glazes appeared to be virtually identical when crash cooled. The sandstone body, also, is an uninteresting greyish white.
left: sandstone/ash 7/3
right: high silica ash / oak ash/ spar 6/4/3
Here are those same glazes after firing for 16 hours and cooling slowly in the kiln for 36 hours. (first two pics are same glaze and body as the ring on the left, above. Second two pics same as the ring on the right.)
norsandstone/ash
Notice a difference? Not only in the quality of the glaze surface, which is distinctly more blue with patches of sugary white, but also with the clay body color development?
nor
The changes in this glaze are even more pronounced. No longer a colorless clear, but a soft creamy white translucent.
Last is a black glaze which was a featureless glossy black on the test ring, but which given time, developed into a rich black/brown with some crystal growth.
So, with that in mind, I wonder how nice these glazes and clay body would look after a 96 hour cooling period in the wood kiln?
On an aside, here is one of five toggle buttons I made and fired in a saggar with rice husks and cockle shells. Same body as the cups above 70/30 sandstone/Izumiyama porcelain. Approx. 6cm
When I decided to learn and make Karatsu ware, I had no idea what I was getting myself into. I knew it was several hundred years old, and the first glazed ware in Japan, but I mostly just saw some beautiful pots and thought I could reproduce. Boy, was I wrong.
I’ve been working at it for more than 10 years now, and the clay, glazes, and firings are still mostly a mystery. Trying to capture the look of the traditional ware is a continual challenge, forcing me to forget or ignore modern technology in favor of archaic, and examine 400+ year old shards, searching for clues about what the old potters and craftsmen used, and how they approached their art, which they didn’t necessarily consider to be art.
The closest I’ve come yet to a surface like the pot at the beginning of this post.
One thing I’ve learned in this time making pots is that despite the primitive technology, ancient potters had knowledge about their materials and handling of those materials that far exceeds the knowledge of most modern potters. This is what makes tradition such an important repository for us. It is the best of what has come before, proven over time and distilled for us to use. We just need to pay attention.
Chosen Karatsu teabowl, late 1500’s
Chosen Karatsu guinomi by author
Cheers,
Karatsupots
Mike @ Karatsupots
Making attractive, cool, useful stuff out of dirt since 2006.
I made a trip out to the mountains in Minamihata yesterday with my mentor to collect materials for pots and glazes, and we stopped by an old kiln site as well.
We were able to collect a good amount of feldspathic sandstone, weathered feldspar, and the ever popular grey stuff (don’t know what its real name is).
First, here is what we collected that will become pots and glazes this year:
The lot of it
Grey stuff. This is softer than rock and can be stamp milled or pot milled easily into a fine slurry. It has a lot of iron, and I use it as a glaze ingredient, as a slip, or as a pigment for decoration.
Sandstone. This has more iron than I’d normally like, but beggars can’t be choosers. It takes the place of both feldspar additions to clay bodies as well as grog. I like it because it helps the body vitrify, but gives it texture as well.
More sandstone.
Glaze stone from near Okawachiyama. I’m not sure but I believe this is the glaze stone used in Nabeshima celadon. I look forward to testing this.
Closeup. You can see the feldspathic translucent pieces in the matrix, surrounded by the white powdery matrix. I think the white powdery part is high in silica, but again, need to test.
Found this in the same place as the Nabeshima glaze stone. This looks to be more pure feldspar. Very curious to see how it fires!
On the way to one of the collecting sites, we passed two old Karatsu kilns, Fujinokawachi and Kayanotani. I was surprised because they are separated by no more than 70 meters or so. These were big kilns. Kayanotani was a 22 chamber climbing kiln 52 meters long! Between them, there were probably hundreds of potters working. We couldn’t really access Fujinokawachi, but we were able to walk around on the hill where Kayanotani once stood.
Access to Kayanotani. You can see the faint grassy steps up the hill, just to the left and down a bit from the tree.
Sign board standing at the entrance to the kiln site. The shard pile extends up and down the hill to the left of the sign.
The outside surfaces of some coil and paddle flasks. Fujinokawachi and Kayanotani are both known for their fine coil and paddle work.
Interiors of the same. Note the different clays used and the different patterns created from the paddling tools.
Hillside littered with shards and chunks of kiln wall and kiln furniture.
The feet of some ash glazed bowls. The clay is quite light in color, and really vitrified.
Detail of some flask lips. On the one, you can see some bubbling in the glaze because the clay body started to bloat. The coil and paddle clay bodies were quite varied, but much of it seemed to contain high amounts of organic matter
More bowls. One in a light clay body, the other much darker. Again, vitrified and hard. All of the trimmed pieces I found were trimmed with an economy of movement. There is no wasted time in the trimming here.
Detail of another foot. Gorgeous clay, and lively trimming.
Interior detail of bowl directly above. Note the beautifully folded over and compress lip of the piece stuck to the inside here, and the glaze window.
Paddled Chosen Karatsu flask. I wish I could get those blues!
There is an old story around here about Nakazato Muan (12th Generation Nakazato Tarouemon, Living National Treasure) finding a really great white clay seam in the Azambaru area of Taku. Here it is in Japanese for those of you who can read it:
For those of you whose Japanese is a bit rusty, it goes like this:
In the year Showa 21 (1946), the Nakazato kiln was converted from a coal burning kiln to a wood burning kiln, and it was fired until Showa 25 (1950). During this time, Muan mostly used a white clay from the Azanbaru area of Taku. There is a story, told by his son Shigetoshi, from the day they discovered this clay seam (Nakazato Shigetoshi passed away in 2015, at the age of 85, so he was probably around 16 years old at the time of this story).
So they have all this clay loaded onto a cart, which Shigetoshi is pulling and his father Muan is pushing, to Taku train station.
On the way, they reach a downward slope, and without noticing, Muan keeps pushing down the slope, and they almost run into a car speeding down the road. Shigetoshi ends up diving to avoid the car, the car ends up in a rice field, and their cart ends up broken. When Shigetoshi gets angry and starts yelling, Muan says “I was so busy thinking about what I was going to make with this clay, I didn’t notice the slope.”, apologizing to Shigetoshi.
“That was the first time my father ever apologized to me.”, Shigetoshi commented.
So why, you say, are you telling me all of this? Well, the fabled white clay seam has been looked for now by other potters for decades with no luck, but due to a fortuitous event a few months ago (and several years of looking), I believe I have found it again. Here are some pictures from our excursion out to dig some sample material for testing.
This looks promising, with the moss scraped away.
Making some progress, this small hole yielded over 100kg of clay.
Two partners today, one is my mentor, in the foreground, the other a friend and fellow artist.
Under better lighting. Isn’t it gorgeous?
Oh, and lastly, here’s a picture of one of Nakazato Muan’s coil and paddle built jars. This one is made from white clay from the clay seam pictured above. My firing tests have almost the same color as the unglazed bottom section of this jar (although it is hard to see from this dark picture).
This firing of the kiln went too long, resulting in Orton cone 11 flat. Ideally, it would be cone 11 touching, then sagging a bit.
Upon unloading the kiln this morning, one thing was immediately apparent: the right side was far more reduced than the left. Yellower glazes and more slumping. Even on the left side there was some slumping, because of the excessive temp., and because of the clay which contained some low temp high iron clay to help seal the ware against leakage.
Left side, sagging only slightly, white surface.
Right side sagging badly, white glaze turned yellow.
Chosen Karatsu came out pretty good, but the white was on too heavy, running down the pots too much. It still came out looking ok because of the clay.
Most of the teabowls warped or sagged, so I only get to keep 2 or 3 of the 15. This is why teabowls are expensive, kids…
All in all, not a bad firing, but need to adjust clay bodies, and pay closer attention to cones. Also, figure out the over reduction on the right side. It might be that one burner that sounds a bit off.
Kakewake CG bowls
guinomi, need more sand in the clay
crystals, only grew on the right side, where reduction was strongest.