All posts by KaratsuPots

Fun with some new clay

Tried out some new clay yesterday. It’s one of the ‘waxy’ sandstones that I dug a couple months ago, the one with the mystery green inclusions. Actually, the pure sandstone turned out to be unwedgeable, so I mixed it with some Karatsu white clay, about half and half. It turned out to be reasonably throwable, with some unexpected chunks and tears.
I trimmed the guinomi this morning and got some nice surfaces. Looking forward to see how this clay reacts to the glazes and the fire.

A beautiful morning

Took the dog out this morning for a walk. It rained all day yesterday and still cloudy and misting a bit today, may be in for more rain this evening. Anyway, cool and subdued, the low clouds hang in the valleys and the treetops like a soft blanket. When it’s early and like this, it’s almost like the outside world is muffled, and the immediate is drawn into tighter focus. It has the wonderful rain smell and the flowers stand out in the lush green. The dew brings all of the spider webs into view, really shining in the patches of sun that come through. All in all, a great morning to make good pots.
My neighbor’s old home. The land is all that remains now, and from the size of this little island of land surrounded by rice fields, I don’t see how a house could have fit there. I’ve been meaning to ask them about this. To give perspective, the hydrangea in the right of the picture is about 5-6 feet high. The old pots have been sitting there in the same place since I moved here 5 years ago, and I imagine they’ll be sitting there much longer. People use these pots for various things, from grain storage to oil and drink storage, to pickling, to human waste containment (which was later used on the fields for fertilizer).

I love this persimmon tree. Looks like a bonsai (with fruit and leaves actually to scale) to me. The persimmons are ripening now and the leaves are starting to fall. My neighbor has a very tall persimmon and uses the old method of getting them down. He cuts a piece of long bamboo(24″ plus) and splits the small end so it’s open a 1/4 inch or so. He can then stick it up under the stem of the fruit pinching it in the split end. Give it a twist and the fruit comes free, but doesn’t drop and smash because the stem is scissored between the split ends of the bamboo. Pretty clever.
A nice little dew covered flower. These were popping up everywhere at the edge of a field that used to have a house. I suppose whoever lived there before planted bulbs, and they’ve been coming up ever since, even though the people are long gone.

I’ve posted a couple more pictures of the accomodations I’ve negotiated for the kiln building workshop next October. These are posted at:

Clay Talk

Did some clay collecting over the past few weeks and have started processing it into usable stuff. It’s all pretty much sandstone. I don’t know the technical terms, but I group the sandstone around here from ‘dry’ to ‘waxy’. Meaning when you cut into it with a pick you’ll get a waxy shine on the cut surface, or just flat dry and powdery. With the waxy stuff, you can usually get some good sandy clay from it. The dry stuff is good on it’s own as an additive for augmenting your other clays, especially if they don’t mature and leak, the added sandstone seals them right up, without fluxing them too much (if you stick with the whiter sandstones)

The pictures below are of some of the waxy type sandstone, after it’s been dumped in a jar with water and mixed with a power drill mixer. It melted readily into it’s components, no mashing or pounding was necessary prior to mixing. The first picture shows the finest particles, which I scoop out after agitating and allowing to settle. This is the finest clay with the least amount of iron. I’m not too picky here, so I get a bit of the finest sand at the same time. This makes the clay very nice when trimmed soft, and if I just took the finest particles I’d waste too much of what I dug up.

Next is the picture of what I get after sifting through 20 mesh. This will be useful in this clay body as an additive of some larger particles. Also it can be nice adding to other clay bodies, especially some store bought stuff that may not be so interesting, just remember to test first before you spend a bunch of time on a large batch.

The last bit is what didn’t go through 20 mesh, fairly uniform granules for the most part, with some larger pieces of sandstone left over. This particular stone has some interesting green granules that I’ve never seen before. It seems hard but crumbles reluctantly if you press firmly with your fingernail. This size is good to hang on to, just in case. The last picture is of some of the dry type sandstone after I’ve stamped it in my man powered stamper mill. This is a fairly uniform mix now, and can be added to finer clays to give them tooth and help them mature.

Just in case you’re wondering, I do find clay that is actually clay and use it too. Right above the place where I dug the sandstone from the pics above, there was a 5″thick seam of fairly white (light yellow?) fine clay. This is named Stephen’s Clay, after my friend Stephen who discovered it. Although fine, it’s not a nice plastic clay, but rather the consistency of wheat flour, if you wet it thoroughly. Should make some really nice pots though!


In the Japanese pottery world, the word ‘tsuchiaji’, lit. ‘flavor of the clay’ is a much used term. In the case of Karatsu, even more so, though I wouldn’t be surprised if Japan’s long, rich history of unglazed ceramics is the main reason this term is so important.

Possibly the most distinctive characteristic of Karatsu ware is the clay, and one thing you might notice when looking at the ware is the lack of glaze on the foot. It’s probably safe to say that most potters (in the world) pick up pots and examine the foot first when viewing a pot, because it says a lot about the potter who made it. Most of the Karatsu potters and collectors I know do this, not just to view the carving job on the foot, but also to see the clay that was used.

The clays found in Saga prefecture, including the Kishidake area close to Karatsu, are usually quite large particle, non-plastic clays which contain a lot of sands. Lots of sandstone and coal throughout the area as well. Many potters (modern and historically) use sandstone in their clay body to seal the body, since many of the clays will not mature even at higher temperatures. Not only are many of the clays quite sandy, but in many cases the clay used was actually sandstone, not clay. One contemporary potter uses pounded sandstone for his clay body, and close examination of some old pots has shown that they too might be made of sandstone. One group of researchers travelled to Korea and found a place where similar practices had been utilized for hundreds of years (the name of the place escapes me now). These potters started with sandstone and pounded it in stamp mills. They then seived it into various particle sizes and created their clay body from that. Left over particle sized were used for other purposes such as glaze ingredients, making kiln furniture, etc… so that there was no waste, all of the sandstone was used.

Anyway, the most prized characteristic of many Karatsu clays is effect of ‘chirimenjiwa’ or crepe-like crinkling that occurs when the clay is trimmed soft. This effect is most obvious in the 3rd photo below, top left, in the 3 footrings made of a white, sandy Kishidake clay, from the Hobashira kiln.

In all of the photos below, the pots shown are quite old (400 years give or take). All of the clays have developed a patina over the years and are likely much darker than when they were first fired.