Have you gone back and reviewed Season 1 Episode 7 - All About Yarn? Jane covers yarn count there. Pearl cotton is a mercerized cotton used for embroidery and cross stitch.

So why does a weaver want to use pearl cotton? I have run across many drafts and patterns calling for pearl cotton. Can say 8/2 cotton be used if adjusting for the sett? I know that Jane says we can use any yarn with any pattern but just be aware of the sett. I love 8/2 and have used cotton and cottolin. I tried weaving with Harrisville Shetland Wool. It was ok and the wool draped good. I just like cotton. Thanks.

When I took a semester of weaving, awhile back, we used 5/2 mercerized/pearl cotton for our gamp.

It’s has a shiny sheen to it. Some people like to use it because of that sheen. Baby blankets and towels.

And like Sandra said, it’s also used for other crafts as well which might be the reason why it comes in sooo many more colors and weights.