Well, maybe this is a slight cheat! However, red and blue do make purple, and I have always said that all interpretations count!
This is the front of a book cover and the sample for the 2 hour workshops at Cottenham. It isn't the best of pictures, but at least gives an idea of what we did. The blue shapes are felt made (on the day) using roving and the red/blue are a combination of fibres and fabric.
Cottenham was an excellent event. If you didn't make it this year make sure you do next.