I would also really like to know a bit about this quilt.
Are you color blocks 4.5 inches finished (did you start with a 5 inch charm)?
Did you sew black sashing or apply a black ribbon after the rows were sewn together?
If sashing, did you use a 1 inch sash (to finish at 1/2 inch)? The sashing looks very, very narrow based on an assumed size of the blocks at 4.5 inches. This is really stunning.