Cotton, and why the staple matters
Gauze uses a very loosely spun cotton yarn, which is what gives it that dry, crinkled surface. The looseness is the point: a tightly spun yarn would make a flat, ordinary cloth.
The fabric
Cotton gauze
Several fine layers held together at intervals. Warm because of the air between them.
The air does the work
Two, three or four layers are woven separately and joined at intervals, trapping still air between them. That air insulates without adding weight, which is why gauze is warm in a way a single thick blanket never is.
It crinkles more every wash
Wash it and it comes out more textured than it went in. That is the finished look, not a fault. Never iron gauze; pressing it flat destroys the loft that makes it warm.
Questions about this fabric
Is it see-through?
A single layer would be. Ours are four layers, so they are not, and they have real weight in the hand.
Will it snag?
The open weave can catch on a rough nail or a ring. Wash it on its own or with soft items and it holds up for years.
Warm enough for winter?
As a throw, yes, layered over a duvet. As a duvet cover on its own, it is a summer fabric.