I have a Kona Cotton color card at the shop, and also a Moda Marble card. I'll see if there are 12 shades of the same HUE of blue that would work together.
IMHO it will be the careful selection of the colors that will make this design work. And I know how colors don't always come true-to-life on a computer screen! If you get some fabrics that lean toward purple and others that lean toward cyan you won't get the same effect.
Will let you now what I find.