Here is the finished card back. I hope the blue looks as nice on your screen.
I figured out the violet dilemma. I have been using crimson or magenta shades as my primary red lately and then mixing my own reds with crimson and yellow. So if you take crimson and yellow which make red and then add blue, you get purple! Red +blue = purple. It never occurred to me that purple contained or could contain its contrasting color. Very interesting and intriguing to me.
So, next I mixed up pthalo green and crimson to make my ‘black’. This time it made a perfect indigo! And so about 4 layers on top of the first one of purple later, this is what you have. I could have added a few more and got it darker but I liked it at this point – it seemed very harmonious.
I am happy you can take two of these and rotate one 180 degrees and they will look almost the same. Nice reversible back without having to digitally mirror an image. It isn’t exact for sure. I haven’t decided if I want to put a white border on it yet.