https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/5975617
The Rainbow Pool
I had to cable up a couple of computers in a room today, and while I was working the students were doing some work with marbling colours on paper by floating their pigments and then laying paper onto the surface.
I'm sure Keith will be familiar with the technique, and it certainly made for a very interesting image! Tragically the only camera I had with me was on a mobile phone, but I'm sure you'll all forgive me. Original public domain image from Flickr
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