A couple of months ago, Janine and I were lucky enough to be invited to Korea to speak at a Porcelain conference. We made the most of our opportunity and spent time in Seoul on our way to the conference to visit friends. I also made the most of this once-off, free travel opportunity, to re-visit one of the remote Sericite Porcelain Stone mining sites in Korea. This site dates back into the 1300’s. Sericite Porcelain has been mined there for over 700 years. I have visited this site before during my research trips, so I don’t need to put on my Indiana Jones hat and consult the ancient parchment map to get there. I know the way, at least I think that I do. I do have trouble convincing Janine of this though when we come to unexpected junctions in the track. We are tramping with our back-packs and although I have found my way here before, we just take the time to walk up a few dead ends into the hills, and retrace our steps a bit, before regaining the correct path. I managed to find my way here after the last conference and re-discover the site. I know that I can do it.
I must say that even though I’ve been here before, it’s amazing how easy it is to forget all the details of the way when you are out in the bush. I remember all the twists and turns in the various tracks that I need to follow to get there, but over time, things have change and the bush has grown over some landmarks, however, there are enough clues that come to mind at each change of direction, so that from time to time I recognise specific points along the way and I am convinced that I am still on the right path.
Eventually we find our way there. This ancient site is pretty damaged now, as the stone hasn’t been obtained from here for some time. I don’t know how long, but perhaps a couple of hundred years. However, there is still a small amount of the sericite embedded in the ground. There had been some heavy rain since I was last here and quite a few good large chunky samples have been exposed, so that I had no trouble filling my small pack with a couple of kilos of good clean samples. I hand pick the best and whitest bits from the dross that it is mixed with.
Now that I’m home and have caught up with all my other more pressing life events. I have time to deal with this most recent research. I set about crushing and grinding these new samples. Prior to this, I have only collected a few hundred grams of stone, purely for analysis and academic research. This time I have enough to be able to throw a few pots.
Seiveing the fines from the crusher, before going to the mill.
I put the stones through the jaw crusher and then the disc mill, then finally through the ball mill. If I had more to deal with I would put the slurry out on the drying bed. But as I only have a couple of kilos of material, I put in into the plaster drying tubs to stiffen up.
This turns out to be a really fantastically plastic sericite. I can wedge it up using spiral kneading straight from the drying tub with no ageing. Amazing for 100% milled stone. It seems that Sericite can be as plastic as any other ‘clay’ – even though it isn’t! (clay, that is).
I was very impressed with the plastic sericite from Cheongsong in south Korea. That was the best single stone porcelain that I had ever experienced up to that time. However, I wasn’t allowed to see the mine site or any of the processing that was carried out, so I couldn’t draw any conclusion, other than to say that the experience of throwing it was excellent.
This time I’m absolutely sure of what I have in my hands and on the wheel in front of me as I have collected it direct from the soil with my own hands and done all the processing myself. It is very slightly floppy on the wheel, but this is to be expected for a very pure primary ‘clay’ – ground stone actually, with no ageing. It certainly works infinitely better than an ‘Eckalite’ china clay body prepared under the same conditions. I’ve been there and done that.
I might just add here that I have a batch of ‘Eckalite’ kaolin based porcelain body that I made 25 years ago. It was un-usable straight from the pug at that time. Floppy and useless. However, it has been ageing in the cool dark clay store now for all this time and it is quite plastic to throw with now. As good as anything else on the market these days. I only wish that I had made 10 tonnes of the stuff back then. It would have been totally worth it. I don’t have 25 years left in me now, so it’s pointless speculating as to what might have been.
Any young potters out there interested in materials and porcelain. I’ve done the research for you. Make use of it.
I have no trouble throwing it on the wheel, it is smooth, fine and creamy and stands up well for small items, keeping its shape and not slumping. If only I had discovered this stuff 20 years ago too! It would be amazing by now.
As far as I can ascertain, from what I have been told through translation. Nobody has used this stone for a few hundred years. It has almost archaeological significance, embedded in its remote, hidden hillside home. No-one in Korea has taken an interest in it as far as I can tell. There is only myself and the local Porcelain Museum Director who seem to have any fascination for ancient sericite porcelain. You’d have to be mad to go about doing research like this strictly for the sake of academic interest. It appears that I am that person who is mad enough. So I am going to donate the best of any successful pots from the firing to the Porcelain Museum for their collection. It will be the only pot made from this stuff for the past few hundred years. Here’s hoping that the firing is a good one.
For an extensive discussion of Sericite porcelain, I refer the reader to my book ‘5 Stones’ which details my 16 year research into sericite porcelain around the world.