Working diagram

When I posted a blip of the quilt on my bed someone asked me how it was made. Although a simple pattern it was hard to explain. It is just a dark square, t dark/light half square triangle units and four dark/medium half square units, all blocks the same. They are set alternately with the medium triangles meeting and the lights too to form an interleaving secondary design across the quilt.
It was a workshop taught by Jan Hassard, , now retired.