The harmony square quilt block is such a pretty block but as so often it is very simple to make. It is attributed to Nancy Cabot and is classified as a five patch quilt block. I have made it here as a 20″ block.
five 4.1/2″ light blue squares
four each of light blue and white 4.7/8″ squares
four white 4.1/2″ squares
eight dark blue 2.1/2″ squares
four each of dark blue and light blue 2.7/8″ squares
four each of dark blue and white rectangles 4.1/2″ by 2.1/2″
Making the quilt block
All the 4.7/8″ and 2.7/8″ squares are used to make half square triangles. Place squares with right sides together and mark a line along the diagonal. Sew a 1/4″ seam either side of the marked line and cut along the line. This produces two half square triangles.
Lay the squares out in five rows of five. The large light blue squares are in each corner and in the middle. The light blue/white half square triangles are placed either side of the corner squares to form large triangles and the large white squares are placed in the middle of each edge of the quilt block. the central square is surrounded by white rectangles and then dark blue rectangles.
Begin to sew the squares together in pairs. I think the layout is probably more easy to see once some of the squares have been sewn together. the top and bottom rows are straightforward – sew the squares together across the rows. for the middle three rows you need to sew some of the smaller patches together before you can sew the squares across the rows. Sew all the dark blue and white rectangles together and sew the dark blue and light blue half square triangles together first in pairs and then sew the pairs together to make four patch units.
Once this has been done the patchwork squares can be sewn together across these middle rows and then all the rows can be sewn together to complete the harmony square quilt block.