Sparkly yarn

I saw this new yarn with a reflective thread in it last year but did not buy any.
Now I'm cycling, I liked the idea of knitting a cowl out of it. Went into town and found two balls in the remnants bin at half price in John Lewis. The yarn is so thick, i think it will knit up very quickly and I'll be able to keep my neck and ears warm and add some more reflection when I'm cycling home.