Often when I run across a mystery fiber I can make a pretty good guess by touch, sight or smell, but every once in a while I’m flummoxed, and then I look up the burn test details. It won’t tell you if you’ve got BFL or Corriedale, but it can tell you whether you’re dealing with animal, cellulose or synthetic. With the growing variety of both natural and synthetic man-made fibers, that can be handy.
The chief differences are how it burns (does it melt, burn actively, or self-extinguish), the type of ash or residue it produces, and the smell it generates. I found this video that gives you both written descriptions and a nice shot of each burning. Hopefully it will aid in your fiber detection!
And my superdeluxe Valley Yarns Sheffield came today for the Sally Cardigan Knitalong! It’s so, so, pretty. Dark brown is one of my usual colors, but purple is pretty well out of my wheel house. But I love them together! Since brown’s more in my comfort range, it’s going to be my MC. I’m expecting a very different look than the retro original! I’m gonna go get myself some caffeine and cast that baby on!