This week’s colour poll is about blue. I almost gave up on it, because in searching for screen samples, there was so much variation between all the sites I looked at that it was impossible to find consistency (in precise terms) of even how ‘blue’ cobalt is. I pick out cobalt, because I have always seen it amongst the brands of paint I have as the most true blue, in the sense of not having a greenish or reddish cast. So in the absence of consensus, the colours set out below are the nearest approximation of how I represent the traditionally named blues. I was interested to realise that there are fewer special names for blue, and I hope I haven’t missed any obvious ones out! Just click on the buttons in the chart right at the bottom of the page to vote in the poll.