» Inspired by Terra Sigillata: A New Twist on an Ancient Surface Technique

December 3, 2008

Inspired by Terra Sigillata: A New Twist on an Ancient Surface Technique

: Combining two seemingly different materials (chunky clay and refined terra sigillata) make an interesting combination on this plate by Anne Fløche.

When I think of terra sigillata, I think of the soft, satin surfaces of low-fired earthenware, like Greek red and black ware that still has that great surface sheen. But Anne Fløche has taken terra sigillata in a different direction. She’s allowed herself to use it in a way that goes against tradition, but is true to her own inspiration and way of working. This is a classic example of taking a tried-and-true technique and making it personal. Whether you’re using terra sigillata in a traditional manner or pushing it to try something new, Fløche provides a great tutorial (and a recipe) for making this versatile material.—Sherman Hall, Ceramic Arts Daily

Terra sigillata is a very old and very simple material used by the Greeks and Romans. They used it to create burnished red-and-black wares fired at low temperatures: 1650°-1830°F (900°-1000°C). I fire higher, to 1100°C (2010°F), because I find that my works are too fragile otherwise. There is a balance to maintain, however, because many colors become dull and dense if the firing temperature is too high. I apply the terra sigillata to bone-dry clay with a brush. Broad brushes are particularly useful. To my basic recipe, I add coloring oxides or stains, as one would with an ordinary slip.
	I realize that I construct my slips in so many ways (even adding sand sometimes) that some might say that it is not really terra sigillata anymore. I suppose this might be true, but it is a very simple way of working, and I have not had many technical problems. I also do not leave my clay to settle, as is typical with terra sigillata, to obtain the finest grains. Many of the materials I use are so fine that this is not necessary. Only when I use a raw, local clay or a stoneware clay with grog do I leave it to settle and separate into layers. Fundamentally, the china clay can be replaced by any other clay: local clays, stoneware clays, etc. Each clay has its own nuances.
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Some clays I use on their own, rather than using them in the recipe; however, nonplastic clays may peel. If this happens, I add more ball clay. Peeling may also occur if the terra sigillata is applied too thick.
	My clay body is very coarse, so the terra sigillata sticks well to the surface. A very fine clay might pose problems. If the clay body is too fine, more grog can be added.