Modification Date: 2016-09-30 22:49:24
Member of Group: RV10 AS10
A celadon recipe containing only two ingredients. It affords slurry and drying control because proportions of raw and calcined materials can be varied.
|Ferro Frit 3134||5.0|
This is a celadon that you can tune to your needs. It works well on dark and light stonewares and porcelains. Adjust the proportions of Alberta Slip to Ravenscrag Slip to fine tune the color (more Ravenscrag for lighter color). Adjust the amount of frit to tune the amount of gloss and melt fluidity. Calcium carbonate also works, but may produce more bubbles floating in the matrix. If you fire to cone 11, then no flux may be needed.
You can fine tune the thermal expansion (e.g. frit 3134 for higher expansion, 3249 for lower, 3124 for nuetral).
Since this glaze is 90% clay, you will need to calcine half of the Alberta Slip complement to reduce the drying shrinkage if it will be applied to dry or bisque ware (if applied to leather hard ware it could be OK as is).
(50:50 Ravenscrag Slip:Alberta Slip) at cone 10R on porcelain (right) and stoneware (left).
At cone 10R this produces an overly melted glaze. It also crazes.
On a white stoneware and a porcelain. The glaze is transparent, it has depth and varies in shade according to thickness, breaking to a much lighter shade on the edges of contours.
The outside glaze on this cone 10R mug (made of Plainsman H550) is simply an Alberta Slip:Ravenscrag Slip 50:50 mix with 5% added Ferro Frit 3134 (the Alberta Slip is calcined). This produces a stunning celadon with great working and application properties. Inside glaze: Ravenscrag Slip 90%, talc 10% (a matte having an extra ordinary silky texture). Learn more at ravenscrag.com.
Roasted Alberta Slip (right) and raw powder (left). These are thin=walled 5 inch cast bowls, fired to 1000F and held it for 30 minutes. Why calcine? Why 1000F? Because Alberta Slip is a clay, it shrinks on drying. Roasting eliminates that, a 50:50 raw:roast mix works well for most recipes having high percentages. And 1000F? Calcining to 1900F sinters particles together (creating a gritty material) while 1000F just does not. But note the difference: The raw powder has an LOI of 9% (looses 9% weight on firing). 1900F-calcine has zero%. 1000F-roast has only 3%. So we need 6% less (9%-3%) of it than of the raw to supply the same chemistry. For example, if a recipe calls for 1000 grams of Alberta Slip: Use 500g raw and 456g 1000F roast (500*.94).
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<recipeline material="Alberta Slip" amount="47.500" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Ravenscrag Slip" amount="47.500" unitabbr="kg" conversion="1.0000" added="0"/>
<recipeline material="Ferro Frit 3134" amount="5.000" unitabbr="kg" conversion="1.0000" added="0"/>
<url url="https://digitalfire.com/4sight/recipes/alberta_slipravenscrag_cone_10r_celadon_92.html" descrip="Recipe page at digitalfire.com"/>
By Tony Hansen