What to do with old yarn?
Like many of us, I've collected quite a stash of yarn over the years. The problem is, I know I'm not going to use most of it. A lot of it is yarn that i was either randomly gifted, or yarns that I bought as a beginner that i wouldn't choose now (I mostly knit garments now and I'm very particular about what fibres I can wear due to texture/allergies). I could maybe use some of it on random projects, but there's more than I could feasibly use (easily 50 different types of yarn if not more) and I don't think I'll be motivated to work on the projects when I know i'm just doing it to use up yarn.
I've thought about donating it, but most of it doesn't have labels so i'm unsure of brand, fibre content, weight (i can guess that most of it is 100% acrylic but I don't even know if it's DK, aran etc) and I don't want to dump a load of yarn on a shop that won't be able to sell it. There are craft groups in my area but most of them are a bring-your-own-project kind of deal so they definitely wouldn't have use for this much yarn.
Anyone got any suggestions? I'm UK-based if that helps. Thanks in advance!