We bought these new yarns to weave Thong.
This yarn is a plant fiber blend. It is approximately 90%+ cotton with the remainder perhaps hemp or some other natural fiber. We know it is natural fiber because we did the burn test.
This yarn is an animal fiber with touches of plant fiber blend. It contains wool, cashmere, some silk, and other natural fibers. The burn test has a fast moving orange flame, and the residue crumbles quickly into dust when rubbed between the fingers. Plus, it smells like burnt hair or such. There is no hint of man-made fiber in the mix.