A potter’s glaze testing is never done. You may be asking,
What is a glaze?
or
What is glaze actually made of?
Well, the simplest answer is that glaze is a bunch of naturally occurring materials mixed together. There’s lots of different materials, but the most basic glazes are made of some clay, and a glass former. Colourants can be added in the process, as well as many other materials that create different effects. The process of making a new glaze is rarely easy, or quick and can be the result of months worth of testing, tweaking, and re testing to get the recipe right.
When I make a glaze and it's passed a few benchmarks such as colour intensity and minimal glaze movement AKA crazy glaze dripping, it moves into further production tests. I know you guys love the drips but I'm after a perfect balance of glaze fluidity that doesn't ruin my kiln shelves!
How do you know that a glaze will work with other glazes?
Once I’m happy with a glaze on it’s own, it's time to start experimenting by layering it with my other glazes. All of my glazes are my own creations from hundreds of hours of testing so I have a good intuition for what works, and of course, what doesn’t! That said, there’s still surprises from time to time. Usually, I start by layering it with other glazes on pieces of ceramic tile that I make by hand. I try these combinations on everything from white clay through to the black clay that I produce in the studio. Following the test files, I need to apply my new blends to a vertical surface to test for dripping again as often the properties of a glaze change when layered with another. What better to test than on a coffee mug? It shows me exactly how these glazes will look and perform in production.
Once I have gathered and noted all the information I need from those tester ceramic mugs I start making a batch for the shop! For those mugs with colour combinations that haven't quite hit the mark, ie. I pretty much just don't like the colours, then they go on the shelf so I can look at them and dream up little tweaks that lead to new creations.
After a few months of testing I end up with quite the collection of one off tester mugs so if you'd like to know when these are available to purchase, make sure you're signed up to the newsletter! The ones that make it through to production end up in my store in the handmade ceramic mugs section.
Would you like to know more about the processes behind handmade ceramics in a small studio? Let me know if you do and I’ll share more of what goes on behind the scenes in another post.
Rhiannon