The penny drops, makers and voyeurs, dirty laundry, royal glory, five good reasons, Hephaestus, savant, mash-up and clarity

compiled by Daniel Skeffington

About Surface Therapy

Layering (stories) is the topic for the fourth in the series of glaze and surface related articles. These studies are in response to requests from the JAC readership and intend to be a starting point through the information maze. Our aim is to discuss the origins of types of glazes and surface treatments their context in contemporary clay practice, a brief scientific overview of how the glaze works and also to bring a practical lens in seeking wisdom from experienced practitioners of those surface types we feature.

Layering (stories)

When considering the taxonomy of glazes and surface treatments, a pot that is ‘layered’ is hard to place, as there must be an infinite number of variations in such a category. What is layered? Is it two or more applications of different medium on the one vessel? Can two or three or four applications of the same medium, perhaps slip or terra-sigillata, be layered? Is the nano surface of silver nitrate particles applied to a glazed pot, now a lustred pot, layered? An understanding might be found in an examination of why we do it. Let’s get layered.


Treating a pot surface with multiple applications of glaze, slip, decoration, additives, decals, tissue transfers etc. is nothing new. Historical examples are not as vibrant or overt as our contemporary multi-media, highly narrative work, however they are still significant examples in the ceramic record. In the Quong, Song, Fong dynasty, or whatever, it doesn’t matter which one, an artisan’s apprentice had a bucket of Tenmoku and a bucket of Celadon and a bucket of iron-saturated slip. In his drunken care of a dragon kiln firing one night he layered some of his masters 2nd’s – just to see what would become, and slipped it into the kiln before it got too hot. Out came a spectacular Hare’s Fur glaze and he was immediately elevated to Master status. Nice story, but I made it up by way of introduction to the unknown historical origin of layering. What we do know is that there are some stunning examples of ‘glaze on glaze’ glory in the historical record. Hare’s Fur and Oil Spot are among them and like most traditional oriental glazes are beautiful and often mesmerising. (What is even more outstanding and like Oriental glazes, is that, often the glazes that are fired upon each other are often outstanding glazes in their own right). So a good excuse, my number one reason, is to use layering to create objects of beauty.

In the Ceramics Arts Daily article, ‘Oil Spot and Hare’s Fur Glazes: Demystifying Classic Ceramic Glazes’ John Britt describes the chemical process which occurs when an iron-rich sub-layer is co