This pattern comes from Charlene Schurch's Sensational Knitted Socks (Martingale & Company, 2005). I love mosaic knitting patterns : it's a technique that creates 2 color knitting patterns using slipped stitches and only using 1 color at a time.
For this pair of socks I'm using 2 ply yarn (15 wpi) ; gage 7.5 stitches per inch. Natural black ouessant and white ouessant yarn space-dyed to create a multi-colored yarn. Also, note that I'm knitting 2 socks at one time on one circular needle. I love this technique. For more information check out Melissa Morgan-Oakes book, 2-at-a-time Socks (Storey Publishing, 2007).