Sericite Journal 2 – 5 More Stones
I arrive in Chuncheon from Seoul by bus and I am met at the coach terminal by my friend Mr Jung Do Sub, the Director of the Yanggu PorcelaIn Museum and Research Centre. He takes me to dinner and then home where I will be staying in his studio, attached to his house.
It’s a stunning new architectural space, it is so new that he is still working on it. Brutal, modernist, bare cast concrete on the inside, with a recycled brick cladding on the outside, heaps of double glazed glass facing the southern sun. (This is the northern hemisphere.) The sun comes right in onto the polished concrete floor. The cast concrete walls and roof are over 500 mms thick. I suspect that a lot of this thickness is taken up with some substantial insulation, as it hits minus -30 oC here in winter.
The next day we drive to the Porcelain Centre, where I start work immediately on getting things ready to make some work.
There are a number of sericite porcelain bodies here for me to choose from. The number has increased since I was last here. There are two new ones that I want to try out. When I visit the clay processing facility a few hundred metres away from the Museum. I see one of the new raw materials, the whitest sample, revealed from under a green tarpaulin, just outside the clay stockpile shed. It is actually off-white, but quite pale looking when compared to the standard local sericite that is mined near by. However, when this new white material it is crushed and milled, the whitish raw material in the wet plastic state becomes somewhat darker. This is usual with clays and I’m used to it. It becomes almost a pale khaki, buff beige colour, whereas the local sericite which is slightly greyish white when raw, becomes whiter when wet?
After stiffening, the resulting plastic pugged clay is mid khaki colour. I’m surprised to see that the fired sample from the reduction kiln comes out very pale grey from under the local standard pale celadon porcelain glaze. I’m intrigued.
There is a related material from the same pit that is slightly pinkish in the raw state, but processes to a pale apricot colour. A colour rather beautiful and very pleasing to my eye. This sericite body fires to almost the same degree of pale grey as the white sample, just a little bit darker, when reduction fired with the same base glaze. I’m quite surprised to see how similar they are after firing, just looking at the difference in the raw colour.
I get to try all 5 different sericite porcelain bodies over the next week or so of throwing and turning. The original local sericite that is mined just up the road here is highly vitreous at stoneware temperatures and is prone to slumping, even at the lower stoneware temperature of 1260oC. However, with a small addition of JinJu kaolinised sericite obtained from farther south, the resulting mixture throws very well and stands up to the 1260/1270oC stoneware reduction firing very well. I have discussed this beautiful porcelain body at length in previous posts, so won’t dwell on it again here.
My first mornings work involves me securing a wheel space in the crowded workshop. This is a community teaching facility open to the public. It’s mandate is to communicate the history and beauty of the local porcelain, and to offer that experience to the general public. I’m the intruder here, a foreign oddity, here for just a brief moment in the very long history of this place. So I know my place and ask permission before doing anything. I don’t speak the language here very well – if at all. I rely on the translation app on my phone to get me through, so I’m careful to be polite and not get in anyone’s way. I know that translation app software out-put is full of errors, so I’m careful. Some of the staff have slowly come to trust me with their very basic English as well. This is my 5th visit here, so I am getting to know everyone. Together we slowly and carefully explore a more friendly, trusting, and may I say ‘intimate’ way of communicating in this strange mix of two poorly pronounced and impoverished lexicons, extended by faulty software. What a mix! We manage to work our way through the errors, pitfalls and misunderstandings. Trust and friendship slowly develops. I’ve come to really like and trust these wonderful people. I’m so lucky.
Next, I have to source some batts, get a few extrusions of this special local sericite porcelain body pugged and de-aired. Then I clean the wheel scrupulesly to make sure that there is no cross contamination of other clay fragments under the wheel head and in the edges of the tray. I don’t want to contaminate other peoples work with my experiments here when I toss my turnings into the recycling tubs.
I sort out my tools and start to work up a lump of this marvellously plastic wet mica rock dust. It’s so hard to believe that it is not clay. At least not as we are familiar with the term in Australia. This body might have 10% of Kaolin in it, but that is all. The kaolin is not there to add plasticity. I have used the ‘Jinju Kaolinised Sericite’ that has been added to this mix straight by itself 100% and it is rather floppy and ‘fat’. The Bangsan sericite is plastic enough without it. What the Jinju material offers is not plasticity, but a slightly higher alumina content to increase its firing range.
An aside: Before I left home to come here I packed up three pots to donate to the Porcelain Museum. Pots that I made over the previous 6 months since my last visit here. I made these pots from stones that I collected myself, directly from out of the ground here. I had the resulting powder analysed and it contained only sericite and silica, so I know what authentic, pure sericite mica is like to throw with on the wheel. It can be amazingly plastic. This isn’t always the case though. The sericite that I collected from the ancient and abandoned sericite mine on Tregonning Hill In Cornwall was almost totally non-plastic, As was the siliceous sericite that I collected from the top of Sarri Mountain near Yeoju, here in Korea. The most plastic sericite that I have ever encountered was from Cheongsong in the south of Korea. A strange place, but marvellous clay. It is a pity that it is totally unavailable for foreigners to access due to the difficult personality issues of the manager of the site.
I should point out though that these most plastic Korean bodies are not the whitest. Surprise, surprise there! The whitest sericite is probably the extremely expensive ultra-white special grade of hand sorted Chinese sericite from China, near Jingdezhen. This ‘sericite’ is very hard to get, and not just because of its extremely high price. Following that is the highest white grade ‘Gao Bai Neantu’, version of Jingdezhen porcelain. It is very good, as is the hand-sorted white Amakusa sericite stone body from Arita, but the Amukusa sericite body is not anywhere near as plastic and also a little tricky to glaze fire due to its very high silica content.
Note to self: try a blend of Amakusa white with Bangsan cream. That would be an unholy pairing from Hell! Possibly considered a cultural crime, due to their difficult historical legacies, but it might work well? Each mitigating the short comings of the other. I just might try it in secret at home, where no one will be offended.
To return to my experiences here at Bangsan.
I only get to start throwing by 11.00 am. I begin by making the clay ‘chucks’ that I know I will need tomorrow when my pots are stiff enough to turn their bases. A ‘Chuck’ is a hollow cone shape of fairly thickly potted clay. This is used to support the delicate rims of the pots while they are having their bases ‘trimmed’ or ‘turned’. I throw these chucks on ‘batts’, flat circular wooden discs, so that when I pick them up off the potters wheel, there will be no warping. I want the chucks to be running true and perfectly round when I come to use them. Even so, I usually trim them and tidy them up when leather hard by trimming them with a sharp tool to ensure that they are as perfect as it is possible to get them. By lunch time I have my 4 chucks out in the sun and 3 larger sized bowls made as well.
In situations like this, I always start with the largest items first, then work my way down to the smallest pieces last. In this way, they are all ready for the kiln at the same time. No waiting for the bigger bowls to finish drying and holding everything up. My time here is limited. I only have a little over 2 weeks. I know from past experiences that I can get everything done in time if I follow my work schedule pretty precisely. 5 days throwing and turning, 2 days drying, then bisque firing and cooling, 2 days glazing and packing the glost kiln, one day firing, 2 days cooling and then unpacking and fly out home. It can be done! I know this, as it is my 5th visit here. In China, they don’t bisque fire, but spray the glaze on dry. They also fire over night, crash cool, by opening the door at top temperature and crash-cooling the kiln. They unpack and repack the next day. So a full cycle can be reduced to as little as just 8 days! If everything goes to schedule!
Once the main body of work is thrown, I get to play with the new sericite samples. The apricot coloured one is very nice to throw but suffers from a tendency to split and crack if they are too thick. Too thick in this extreme case is anything over 5mm! This body may be only suitable for very small, thinly potted items, or so it seems? I try my hand at the special school mix that they have developed here that is a mixture of three sericites. This body was developed to make it as forgiving and easy to used as is possible. It is used for all the classes. The Porcelain Museum and Research Centre also has a teaching facility where members of the community, school children, aged care groups, retirees and even squads of Army soldiers come in and learn a little bit about the history and culture of this part of Korea. As complete beginners, the work that they make is sometimes a little bit heavy and somewhat clumsy. The blended teaching clay body that they use for the students is designed to be easy to use, forgiving of lack of technique and indestructible in drying. It works remarkably well. I really like it. I’m not properly trained in porcelain. I’m entirely self taught, so this kind of clay is a great advantage to me as a ‘blow-hard, wanna-be’ potter of average skills and insights. However, I really like the challenge of the single stone varieties, even though they are harder to use. I don’t always get successful results, but I love to learn new ways of compensating for their – and my – short comings and developing new skills in coping with their individual difficulties and character. Giacometti once said that every failure brings you one step closer to success. There just might be some sort of truth in that. If you persist!
The teaching ‘clay’ mix of 3 sericites, appears to be a little bit speckly when I cut through it. I’ll wait to see how it fires. It just might have some iron specks? Although I don’t see any in the students fired works. Some of the students recognise me and remember me from my last few visits. They welcome me warmly. I’m impressed and thrilled to be included in their conversation, even if it is at the most basic of levels. One student even comes up to me and addresses me by name. He produces my book from behind his back and asks me to sign it for him.
The standard body, on the other hand, is rather fertile this time round, with some sort of organic growth in this well-aged sample. This is of course no problem and will fire out in the bisque.
I end my 5 days of throwing and turning with 45 finished pots from the 5 bodies. The apricot coloured clay continues to self destruct day by day afterwards, all I can do is sit and watch.
The pale coloured sericite body doesn’t like being wire cut, it stresses the clay particles too much and they tend to come apart as they dry out and start to shrink. It seems to lack cohesion? It doesn’t seem to be too much of a problem however, as the cracks are only surface splits and they are easily turned out. I have seen cracking just like this in Jingdezhen in their porcelain body, but in that case some batches of the clay are almost impossible to use without significant losses due to high rates of shrinkage cracking. Those cracks transferred all the way through the pot, so there was nothing that I could do to solve the problem. The Jingdezhen clay also has a tendency to chip and tear too, if turned anywhere near leather hard or softer. It benefits by being left a little bit longer to stiffen more, waiting until it is completely covered in the white drying rings, then it turns a lot easier and smoother. The whitest batch of the teaching mix is also prone to chipping when turned a little too soft. Just like the Amakusa porcelains from Arita.
The staff who work here are so professional. Their skill levels are very high. The Post-Grad students who study here after completing their Masters or PhD, are also extremely talented and dedicated. The quality of their work is exceptional after 3 to 5 years of post graduate specialisation in porcelain techniques in this place, they are very accomplished. I can’t impress anyone here with my amateurish skill levels. The thing I can impress is the clay. I use my initials and the Yanggu Seal to represent the workshop where my pieces are made. I impress the seal in to he clay. I love it. It’s such an ancient way of identifying pots, and this is a place with a very ancient tradition.
I am so lucky to be able to work here within this system of nurturing support – as a foreigner, an outsider. The Other! Not from here. These people embrace me and go to great lengths to engage with me and include me in their life, day to day. They include me in their lunch time meals in one of the local family kitchens each day. It has proven impossible for me to pay for even one of these meals. I offer, but no one will let me pay the bill. Everyone here is so open and generous. I wish that I could say the same for Australia’s treatment of refugees! People who really do need, comfort, help and support.
I make a suitable mess all over the floor, as the wheels here don’t have trays. I have no problem in throwing without a tray, I own a Japanese ‘Shimpo’ potters wheel at home, Although I don’t use it often, as I prefer to use the wooden kick wheel for most of my work. However, I have taught myself to use very little water when throwing and don’t ever seem to get any clay slip splatter on me or the floor and I never use a towel on my lap!
But trimming is another matter. I can’t stop the spirals going everywhere onto the floor as they effortlessly peel off from the razor sharp turning tool. I just get used to sweeping up at the end of the day. After I have turned the last of my pots, I sit down and go through them and sort out a few obvious faults, mostly hair line cracks or slight warping. Then I give a little time to examining the forms pretty closely, as well as the weight and balance.
I cull and I cull. Each day I re-examine my work and trash a few more. I go through the almost dried work and cull another half dozen that are not up to scratch. No point in firing something with a form that isn’t as perfect as you can make it to begin with. Ceramics is the ultimate pollution. It last forever. Everything that we know about ancient cultures was dug up as ceramics! It won’t get any better with glaze on it. I will go through them again just before packing the bisque, once they are all fully dried. I may cull a few more!
I’m down to thirty pieces now, some of my forms were not sufficiently pleasing and didn’t pass muster. I’d like to come away with a dozen good exhibitable pieces for showing eventually.
My throwing time here is now ended, and the less interesting period of packing the bisque and bisque firing is coming up. I will have some spare time, so will start to write all this up.
It is such a honour to be able to work here with these amazing sericite materials. To get this unique experience, and possibly get to take home a few exotic, one-off pieces of unique sericite porcelain. Pots with a history that goes back 700 years on this site.
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