Any of you who have been following me for a while might know that I am a contemporary slipware potter… I use coloured slips (liquid clay with added pigment) to decorate my pieces rather than glazes. To date my work has been inspired by the breathtaking turquoise blue that I see each summer on North Uist’s shell beaches. However the sea can be a multitude of colours from blue, to grey, to green and for some time I’ve wanted to expand my colour range to allow for these.
Until now I have been using ready-made slips but I’m finding this both limiting and expensive. To make my own there are two alternatives: to buy manufactured stains, or to blend my own combinations of oxides. One day I hope to do the latter but for the meantime I’m going down the stain route. I’ve been prevaricating about this for ages… Why is it that the things you think are going to be tricky end up being pretty straight forward? Maybe it is as a result of thinking about it for so long that I’d worked out most of what I needed to do in my head before starting.
First I made a series of test tiles out of clay slabs – each one with seven impressed areas to apply the different combinations of colour. Then I made endless pots of slip using measured amounts of dried waste clay, water and stain. These were left to slake overnight and then passed through a fine sieve to ensure a smooth consistency and proper mixing of the pigment. With each colour I did three tests –
Dilute: where incremental amounts of water were added to the slip to thin the colour
Lighten: where additional quantities of white slip were added to fade the original colour
Blend: fading one colour into another to create other colours
126 combinations in all.
There are some results that I really like, and some that need a little finer testing before I achieve what I’m after… but all-in-all not a bad first attempt.