Note the price is for the hat and the scarf set. When you purchase the pattern from Knit Picks or ravelry you will get both the hat and the scarf.

This simple hat features two-color brioche stitch and reversible brioche cables knit with two complimentary colors of the fabulous new Chroma Worsted Weight Yarn. The hat is completely reversible making it easy to match with any outfit.

This pattern is worked entirely in brioche stitch so each row will be worked twice, once with the main color (for all the knit stitches) and once with the contrast color (for all the purl stitches). One ball of each color of Chroma (2 colors, 1 ball each) will make 2 hats.

NB. There is also a pattern for a Chromatography Mittens and Scarf.
http://www.ravelry.com/patterns/library/chromatography-mi...
http://www.ravelry.com/patterns/library/chromatography-scarf