Ingredients

Ingredient Amount
Albany Slip 975.60
Sodium Hexametaphosphate 24.40
Add Amount
Warm Water 8.00

Instructions


I mix these terra sigillata recipes in 1000 gram batches, which require 8 cups of water (add up to 10 cups of warm wate). To make the mixing easier, I use wide mouth gallon jugs, and prefer glass so it is easier to see whether the layers have separated.

At cone 10-11 this sigillata is a natural Albany Slip glaze, which is enhanced when fly ash or salt interact with it. Making it into a sigillata is more for the working properties of a sigillata in the application process than the finished result.

Making Terra Sigillatas

Mix deflocculent (I use sodium hexametaphosphate, a fabric water softener from the Dharma Trading Company) in warm water, preferably in a blender, pour into a container with correct quantity of water and add dry materials. After sieving, ball mill the terra sigillata 6–8 hours to increase the amount produced in a measured batch and reduce waste. After ball milling, let the terra sigillata settle for a week or more in a clear container, ladle off the clear water layer on top, then pour off the middle layer of terra sigillata. A layer of larger clay particles will have settled on the bottom of the container.

This recipe was shared by Alan Willoughby in the April 2019 issue of Ceramics Monthly.