This is a new for 2015 & limited run yarn. Because of the nature of this yarn it is technically fingering weight and can be knit quite densely for mittens or garments but retains its shape worked more loosely for shawls or scarves which is why the large range of suggested hooks & needles.
Rifton is a single ply, fine USA grown & spun wool yarn, approximately 21.5 microns, and lives somewhere between a stripe and an ombré. Each colorway shades between 2 natural undyed wool colors and dyed in the wool (by Jill) brights.