What colour is a blue brick?

Sometimes, work means I have to do some odd things. A few weeks ago, there was an emergency run to buy pencil crayons. Yes, coloured pencils. For the station building project I was working on, I had to colour in some blue engineering bricks. Now, in the past, I'd been told "Prussian Blue" was the colour. I tried it, and it very much wasn't. Far too blue. That being the case, the project ground to a halt until I located the correct colour, hence a hurried trip to my local art shop, Picturesque, in Warwick, with some photos of real buildings. Now, the people running the shop are used to oddballs coming in, and didn't bat an eye at someone testing every flavour of grey in the rack on a bit of card kept from the kit fret. It took a long while for me to work through all the ranges and settle on a selection. The bricks are a lot greyer than you think, but with a hint of blue. Sadly, no one makes a "blue brick" pencil to make things easier for me. In the end, I came away with a few: Derwent…