big spools of vintage string, unbleached cotton or linen nubby textured yarn or thread

Lot of two big old spools of a nubby textured unbleached cotton or linen thread. It's like a fingering weight yarn, or a weaving thread. Not suitable for sewing, I think.

This has a nice soft feel, all natural fiber - I'm inclined to think it's linen as the color is more as I'd expect from that, slightly grey tinged. But it might just be grubby after years of storage! There are noticeable spots on the outside wraps.