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Hi everybody, This is my first post here, nice to meet you all. I have a question about some result of fired colored porcelain. I am making some unglazed porcelain objects, with the goal of having a very matte finish. Now I have made a test with porcelain colored with a black stain, I have added 4 % to the slip. The stain is based on Co-Fe-Cr, it's standard stain I purchased at a ceramic supplier, the same goes for the slip. What I did: First did a bisque fire (electric kiln) until 950 degree Celsius (1742 degrees Fahrenheit) I removed the objects and finished them (sanding) to a more smooth finish In the kiln again, fired until 1230 degree Celsius (2246 degrees Fahrenheit) The result is a matte looking porcelain, but it has some unwanted glossy spots on the surface (see attached photos). I do not understand why this is happening. Maybe somebody has an idea what could be the cause of this? Thank you in advance. greetings, Patrick Hartog

Dears I recently made tea pots based on the old japanese houhin design. Hence it does not need a metal seeve. However, after using them some dark spots appear on the bottom side. Perhaps this is just the color of the tea slowly leaking through. I wonder if it could be an unhealthy fungus. It was fired approx 1250 degrees. For comparision, the inverted teapot on the top right of the photo does not have dark spots. Because it is glazed on the inside as well. Any experience or ideas on that? Thanks. kind regards Zustand

Hi everyone I use porcelain clay and I hand paint each work but I'm looking at making a new series of work that I want use the same drawing in multiple pieces say 100. So maybe a decal or transfer? I want it to be a crisp image and on unglazed work that is fired to 1280 degrees Celsius. I'm happy to apply it at any stage after it's built but would be best on bisque. I can only think of those glossy 80s decals that need to be applied to glazed work, but I want a more seem less matt finish with no outline. I wanted to attach an image to this post as an example but I can't work out how.. Oh and these will it be functional works Thanks Lilly

Hi, this is my first post and I'm so glad to have found this forum! I have only a test kiln, so space is limited. I'm firing unglazed cone 6 porcelain pieces, all cylindrical and of similar size (each about 100 grams fired). I want to stack them directly on the kiln floor without the wares sticking to each other. Initial experiments with imperfect forms suggest that sticking will be a problem in the next iteration, when the forms will be more perfectly cylindrical and have greater surface contact areas. I had thought to use kiln wash on the wares themselves to prevent this, hoping to remove the wash with minimal effect to the finish of the pieces. I could just try this ... but I could also return the unopened bag of wash if, as I'm beginning to fear, the wash will adhere strongly to the wares... The pieces could be burnished or roughed going in, it's no great inconvenience either way. But power grinding post-vit would be over the top. Maybe some other substance would suit this purpose better? (This kiln wash is the standard 50:50 kaolin:silica combination.) Ideally, the wash would crack off like a husk, with no bonding interactions with the wares whatsoever. Just read about "shelf paper" for the first time today, and maybe some corrugated wrapping pattern with that stuff would work better? Or would it still bond?... (Today I read in a post on this forum that it's only used for glass, so probably bad idea? And then I read that you could use it but it's a particular health hazard?) Maybe the finish including bonded wash, with a quick sanding, would be acceptable. I could sort of stilt the pieces, placing little interstitial balls of clay -- pretty labour intensive loading, but that would reduce the contact area. But then sagging might be a problem there. Any suggestions will be savoured! Andrew