This silk thread, sold in 25 yard hanks, is primarily used for embroideries but can be used to weave small-scale tapestries, crochet accessories like snoods, braid into cord, or weave trims as well.
The color is achieved with a species of Phragmites (common reed) that is threatened in Europe but problematically invasive in North America. It's extremely seasonal, only useful within days of the purple tops opening, but very eco-friendly on the craft dyeing scale in the US as cutting this species down is helping native wetlands plants not lose out!
It's a curious sort of color, almost yellow in the sun; in the shade, almost like ash blonde, but possibly a little too saturated for that? It is particularly difficult to try to capture on camera.