The photo of the inside of the my kiln shed is a glimpse of my night time work environment. This is the place that I visit at very frequent intervals through the night when I am firing crystalline glazed pots. When a kiln is firing, I take advantage of the heat of the kiln exterior to dry pots.
My little studio gets filled up with buckets, bottles and sieves when I am glazing pots.
This is what a freshly glazed pot looks like. This one has a crystalline glaze applied to it. "But where are the crystals?" you say.... !
When I am glazing crystalline glazed work, I often start by dipping or pouring glaze, but then I build this up to a much greater thickness of glaze with a brush. The glaze needs to be up to 3mm thick in the top quarter of the pot, and progressively reduced in thickness towards the foot of the pot. Brushing the glaze helps me control the glaze thickness, and this is quite a long job on a big pot.
|The crystals range from about 1 inch to 2 inches in size.|
Here is a close up of a vase that came out of the kiln on Wednesday Morning. Before it was fired this glaze looked rather like the one in the photo of the freshly glazed pot. This glaze contains lots of zinc oxide, and, with so much zinc in the glaze, the crystals happen naturally. As the crystals grew they collected some cobalt carbonate from the glaze and turned blue. When the crystals were growing, I held the kiln at about 1075 Celsius (1967F) for three hours, then raised the temperature to 1135 Celsius (2075F) for a further two hours, this gave the crystals a dark blue centre surrounded by a paler grey.
|Vase 380mm high (15 inches) by 250mm wide (8 inches)|
I like to create a deep pool of glaze somewhere on a pot, and letting the glaze overflow like this really shows its liquid nature. Even at room temperature, it still looks wet!
My latest pots feel at home by the sea.