Hi walkingthedog, thanks for replying. The only Nanking Blue I've found is by Railmatch and, yes, I'm trying to match the colour on my 50+ year-old trains. No other blue paint that I've looked at is anywhere near Nanking Blue but the Railmatch is a few too many shades 'bluer' than the trains. I'm thinking of trying to mix in a drop of dark green or something.