Iwas about to give the answer royal blue, but treetops beat me to it. also I have yellow for another answer, so I'm wondering if yellow is correct for no 47.
Thanks treetops-Indigo was in my list of colours that I'd made when I started the quiz, but hadn't used because I couldn't see where it fitted in, so thats great,but I've now run out of colours with 6 letters, which is why I can't get no 41.