New pattern alert! I saw this on one of the FB forums and asked if she had a pattern. She didn't but this was what she said "I made this using a photo from Pinterest as inspiration.
I worked out that there are two sub-blocks - four scrap squares sewn in a 4-patch and a grey and white half square triangle (HST). A block is a 9-patch made up of 4 of HSTs and 5 of the scrap 4-patches. The HSTs are arranged so they have a grey side against the centre scrap block and so the diagonal lines all run in the same direction.
This QS quilt uses 36 of these blocks, and I arranged them to make the grey and white concentric diamonds"
Wow- so much easier than I had thought - so I will be working on it!