Ingredient Amount
om-4-ball-clay-(in-pounds) 14.00
Water (in gallons) 3.50
sodium-silicate-(in-tbsp) 2.00


Weigh and add the water to a larger clear plastic container, which will serve as the settling container. Add the dry clay to the water and allow it to slake into the water. Blend the clay and water using a drill with a mixer attachment until it’s thoroughly incorporated. Add the deflocculant slowly as

the drill continues to blend the clay, water, and deflocculant together. Let the mixture sit for 24
to 48 hours to let the heavy particles sink to the bottom of the bucket, then siphon off and collect the light stuff above the layer of silt on the bottom. The silt layer can be discarded. The resulting terra sigillata should be silky smooth to the touch, as it is made of only fine clay particles. I leave this in a bucket and mix it individually into jars with Mason stains that become my colors. I apply my terra sigillata in a blotting method with a sponge similar to the technique used by Candice Methe (as seen on YouTube). I like the way it applies and also the way it layers itself, which adds more depth to the surfaces. I also like the way it looks with my liner glaze when it’s not smooth.

I found my terra sigillata recipe online, and it is also included in Rhonda Willers’ book, Terra Sigillata: Contemporary Techniques. If you’re thinking of doing anything with terra sigillata, her book is the best resource I have found. 

This recipe was shared by Michael Griffin in the February 2023 issue of Ceramics Monthly.