The light hank is 100% cotton. I always thought cotton would be really hard to spin. It's not. It's definitely more slippery than wool, but it isn't like I couldn't spin it. I haven't knit it up into anything yet, maybe a summer top? The medium is a coopsworth wool. EASY to spin. It is a bit scratchier than I'd like, but it was a joy to spin. Because it isn't super soft I'll probably use it for a blanket or something like that. I was a bit disappointed when it arrived in the mail, I ordered it thinking it would be more of a garment type of wool. Live and learn.