Hello everyone,
Longtime lurker, first time poster
I have a bit of a strange question, or rather a desperate plea for help. For the last year or so I’ve been experimenting with a talc based clay body (fired to cone 6). It’s an odd one, but has some very interesting properties and I love working with it. The only problem is I can’t make it hold water for the life of me, so I’m hoping someone knowledgeable might have some ideas. I mostly do sculptural work but I would love to be able to make a vase or plant pot from this clay.
The recipe is 60-65% talc, and as for the rest I’ve tried a few versions but let’s say 60 talc, 20 kaolin, 10 silica, 10 ball clay. Have also done variations including cornish stone, wollastonite, alumina etc, keeping the talc content at least at 60, and kaolin pretty substantial.
It has some unusual responses to glaze, which is partly what I find so fascinating about it. Most gloss / satin glazes will cause the body to crack, while some of them just turn matte. Funnily enough the only gloss glaze which fits is Britt’s snowflake crackle, it doesn’t crackle at all on this clay. I have so far achieved one single tiny test pot using the snowflake glaze which does hold water. It was very exciting! But the problem is, if there is so much as a single pinhole, water will go right through it. Reglazing doesn’t necessarily help either.
I’m desperate to find some way to make it watertight. I don’t suppose with that amount of talc there’d be any way to vitrify it… I wonder if there are any engobes or vitreous slips that might do the trick? I’ve even heard of an old technique of “curing” earthenware by soaking it in boiling milk, which I’m starting to wonder about! At this stage any and all ideas welcome and greatly appreciated