Loupes, rubber gloves, careless washer-uppers, subversive gurus and Janet’s ‘wonder glaze’

compiled by Daniel Skeffington

About Surface Therapy

Glazes for Functional Ware is the topic for the third in the series featuring historical perspectives, Australian contemporary use, basic theory and science, further reading references, and a working recipe for you to try. And there’s a new barrier product which enables unglazed bisqued work to be used as if glazed – a development that adds wider scope for more genres to be used as functional ware. Featured artists include Janet DeBoos (ACT), Michelle Lim and Ng Seok Har of Mud Rock (Singapore), Prue Venables (VIC) and Paul Davis (NSW).

Glazes for functional ware with a focus on wide cone range firing

Even a short time spent researching this topic in the literature or on the web would scare the pants off the inquiring potter considering using or developing a glaze for functional use. If we’re not poisoning our users, flakes of glaze might be ingested, lodge in our bodies and become internal cancerous alien monsters – worse, we might poison ourselves at any point of the many steps in making. And even worse still, the glaze we use might not be ‘fit-for-purpose’ – and we don’t want Fair Trading breathing down our necks, do we?

What is difficult and of primary importance in making functional ware (sometimes referred to as domestic ware or dinnerware, both limiting terms which deny the many other functional uses for ceramics), is to use a glaze that satisfies a whole bunch of criteria including, and other than, health and safety issues. These will be discussed here. Further still, if you’re a beginner or have little firing experience, when facing these maker dilemmas you want to start by using a glaze that is tolerant of a wide firing range and also has application on a diverse range of clay bodies – as an insurance for your work’s successful completion and perhaps to make your world a little less stressful. For functional ware, the successful outcome of the surface treatment you will choose for your vessel is ultimately to have ‘utility’ as its core DNA and to be either facilitated or complemented by that surface treatment.

Functional ware beginnings

There is a toss-up amongst scholars of antiquity as to the purpose of the first man-made clay objects. Were they objects of belief and ritual expression? Think Venus of Dolní Věstonice {1} (29,000 – 25,000 BCE). Or were they vessels to carry water from the stream to wash down Mum’s woolly mammoth stew? Whatever the functional purpose first devised, functional ceramic objects have existed throughout the millennia. And it’s now gone full circle with designer ceramic watches! The ceramic material has an enduring currency. Alongside this development pathway there has been an ever-increasing set of criteria in the making of functional ware – from a volume-holding vessel to a non-leaking vitreous body to a product that doesn’t go KaBOOM! when nuked in a kitchen microwave, or an item needed to colour-match the board’s dining-room