I got all 20 blocks sewn yesterday. They don't excite me as much as red, orange, pink and yellow does. It will be an 'OK' quilt though.
I was cleaning off a shelf in the basement and I found this 1975 booklet. It has you cut 6" squares, sew them right sides together with a half inch seam, turn and insert a double layer of batting cut 7" with the extra fullness in the center. Then hand sew the opening closed. Then they are all whip stitched together by hand to make the quilt. We have come a long way since then!!
Here is another quilt from the booklet with corduroy used where it is red. There is another one in the booklet that is made of all velveteen, and still hand whip stitching all of those squares together.
This is a piece of fabric from the 1970s and I have a yard and five eighths of it. It is by Thompson of California which I think was a swimsuit company back then. 
I laid my 45 mm rotary cutter on it so you can see the scale of the print.
This is the weave of the fabric. There was a name for this fabric but I don't remember what it was. The threads lay across the surface kind of like a sateen but a little more space between them. Maybe someone who reads will remember the name of the type of fabric. Added later: this is not bark cloth which has a slub and is bumpy. This weave is smooth and a little silky.