This pattern was previously available as a Mystery Shawl at http://groups.yahoo.com/group/GalKal. As of right now, only the square version has been compiled into a PDF.
This pattern comes in two shape options (square or triangle) and three size options (small, medium, large). For the large sizes, I estimate about 3000 yards for the square shawl and 1500 yards for the triangle. I used a lace weight silk from an Etsy seller, but any lace weight yarn would work. I personally think a heavier lace weight looks better.