from Magknits.com:

Silk is lovely to knit with, except for how it isn’t. It’s soft, it slips through the fingers nicely… and it’s just not as stretchy or as easy as wool is. This pattern for wrist warmers is a good way of starting off on silk. The main lace pattern is bias with some cabling, making the knit tighter and clingier than it would otherwise be. For the same reason, instead of regular stocking stitch, the ribbing, thumb and knuckles are knit through the back of the loop.