Sgraffito slip decorated pottery
This is now my preferred method of decoration; it is a beautiful art form and avoids the environmental problems associated with smoking out the neighbours!
Scratched Pots – known as Sgraffito, from the Italian ‘graffiare’ meaning ‘to scratch’.
These are made by the same methods as my other pottery except for the plates and saucers which are made by rolling out clay sheets to a thickness of 6mm and pressing them onto plaster moulds that I made.
The pots are constructed from red earthenware and coated with a brushed on layer of white earthenware. When almost dry a design is scratched through the white clay to reveal the original red clay underneath.
After the biscuit firing of 1080°C the pots are glazed with a transparent borax based glaze fired on at 1100°C. This glaze brings out the whiteness of the brushed on layer and changes the red clay to a rich brown, a most decorative contrast on the pot.
The technique of sgraffito is as old as pottery itself and is practiced all over the world. The Bideford Pottery in North Devon has been famous for its scratched ware for centuries and many fine examples can be seen in museums around the area. The pottery is still in production making domestic ware and souvenirs which they glaze with a clear honey coloured covering. It's a warm colour and by adding 6% of iron oxide to my glaze I obtain a similar result which I use on some of my pottery.
To scratch through the white layer of clay I use a metal pointed tool; to produce thin lines I use a needle held in a pin vice and to remove broad areas I have modified a scalpel blade.
The most important aspect for success in this method of decoration is to carry it out while the clay is at the correct level of moisture. If it is too dry, the clay will chip off as the metal point drags through it. If done when it is too wet the clay curls up rather like butter does on a knife. In the correct condition the clay comes away and leaves a clean line. Any mistakes can be covered over with white clay at this stage. Sometimes I use underglaze pigments to add colour to the designs.
This slideshow shows my own method of applying sgraffito to a pot.
I enjoy this method of decoration as it allows any subject matter to be transferred onto pottery, from simple freehand designs to more detailed work requiring careful controlled application.