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So I know there are a few of you UK members out there who work with bone china slip. There are hardly any Americans making and using it and I want to learn. I've picked up my raw materials and have a basic recipe of 50% bone ash, 25% Cornwall Stone, and 25% kaolin but finding out /more/ details isn't easy. The initial firing temps listed are super high at 1400 C (Orton cone 16), too high for my kilns that only go up to cone 10. I understand that adding fritware can lower the firing temps into a more workable range for me of say, 1250 C (2282 F or about cone 8). But I am not having any luck yet finding which fritware to use and how much. Anyone willing to make suggestions or have a bone china slip recipe with more detail that you might be willing to share? I currently have my bone china sculptures produced in England and I coudn't be happier with them except for the expense, and the fact that I may have a 1 to 2 year wait to get pieces done and shipped to me for glazing. I am blessed with a local supplier that carries everything I need - except again, I'm not certain /which/ kaolin is ideal for bone china slip. The one I got to try first is Grolleg English china clay. The Cornwall stone here is more orangey tan than expected and seems to be low in flourine, which I hope won't be a problem.

Hi there. I have bought this glaze : https://www.potterycrafts.co.uk/Products/potterycrafts-stoneware-glazes/P2813 (firing range 1180 - 1250 degrees C). I have applied it to stoneware clay that I bisque fired at: I have been doing this for bisque: Section 1 - room -> 600 at 90 degree per hour Section 2: 600 - 1000 at 200 per hour Could anyone reccomend a firing schedule in degrees celcius per hour for me? I use an electric kiln. Will I need a soak or anything? Thank you, Lara

It looks like some of my shelves are hitting temp but kiln sitter hasn’t been triggering auto shut off (pyrometric bar melting). Please advise TIA!

Newbie here. I started in November and have fired my kiln four times (2 bisque, two glaze) with pleasing results. I use Amaco Stoneware Clay 38. Typically I fire it to cone 7 (I was shooting for cone 6, but my kiln fires hot). Recently I found this info connected to the clay I buy: "Bisque fire to Cone 04 (1971°F, 1077°C). The firing range is Cone 5–10 (2205°–2381°F), and the recommended glaze firing is Cone 10 (2381°F). At Cone 5 (2205°F), shrinkage is 13% and absorption is 7%. At Cone 10 (2381°F), shrinkage is 15%, absorption is 1.4%, and the clay fires white in oxidation and gray in reduction, both delicately peppered with darker gray spots." So my question is this: What does "recommended" mean to the fired pieces I've already made? Should I change my firing range to high, rather than mid level? What about the cone 6 glazes I've been using? If I begin to fire at cone 10, should I still use the Amaco cone 6 glazes? What does cone 6 vs cone 10 mean in terms of glaze usage? ...and is it even necessary to change courses? TIA