All the books I have, when discussing dyeing with onion skins, use brown onions. So I thought I would use red onion skins and see what happens. Quite the surprise, the dye bath was purple/pink, the yarn after boiling and cooling was purple/pink (forgot to take a photo unfortunately), not sure when it changed exactly, but after wringing and washing got mustard yellow. I don't know if it was the air that changed it, the tap water, or the wool wash, or thats the way it just is. It's a lovely yellow.