This is the double 4 patch block, done in reproduction Civil war era fabrics. With a number of these blocks set together, the light squares make a sort of "path" through the quilt.
I made this quilt square myself, and it finishes at 4 inches. I feel a little uncomfortable putting others' quilts or diagrams up here - they are not my work. So I guess after this month is done I'll have a little collection of quilt blocks that could make a baby quilt!