This set of photos documents the first technique I tried with the concrete. This is a technique that had already been established to print a clear image by Tracy and Alasdair and so was a good starting point to establish a familiarity with the concrete and the oxides that we were printing with.
For this process we mixed the oxides with medium and printed the images like normal screenprints with the idea that the medium the oxides were suspended in is burned off in the kiln leaving only the oxide behind. The oxides were slightly difficult to work with solely because it was difficult to judge the ratio of oxide to medium in order to get an image that prints but doesn’t bleed when fired. When fired the oxides also change colour so judging colour schemes was tricky too!
I went through a number of stages with this piece of concrete:
I was provided with a slab of concrete that was ready to be printed on.
I created a toner wash drawing that had a number of different marks (dots, lines, hashes, washes), and exposed image on a textiles screen.
The first layer of oxide was a red underglaze, as you can see in the later photographs when fired this turned a rosy pink. This may be due to too little oxide to medium but I have also been told that if I glaze it completely it should turn redder.
The second layer was a marbled mixture of manganese oxide and iron oxide, I drizzled the manganese onto the image on the screen then pulled the iron over that.
After this the concrete was fired in order to see the colours I was working with. The benefit with refractory concrete is that you can fire it as many times as you need.
When I was able to see the colours they seemed rather pale so the third layer of oxide was another marbled mixture of manganese oxide with a black underglaze.
We then experimented with different ways of applying glaze. I tried silkscreening the glaze onto my concrete so that I would be left with areas of matte and gloss. This was only partially successful as when printing the liquid the glaze did pull through the screen but we think the actual glaze itself didn’t pass through the mesh of the screen. So maybe using a bigger mesh or just pouring/spraying over a stencil would work better.
I like the matte finish with only slight bits of glaze but when I try the next one I will consider my oxide choice more carefully as some are less durable than others.