From KnitRowan.com website:

This luxurious scarf, designed by Sarah Hatton, is great for adding a touch of elegance to an evening outfit during the cooler months. Knitted in Kidsilk Haze Vintage, a vintage look yarn, it makes for an excellent addition to any wardobe.

Yarn is worked with diagonal shaping, increasing one stitch at the beginning and decreasing one stitch at the end of each RS row.