A while back I was making dryer balls and there was a mishap. I used fisherman's sweater wool, which met all of the criteria. I was having a bit of trouble with the felting, but decided to just put them in the hot washing machine. I've been making them for a while, so I was pretty confident. This was the result. I worked at the knots for a great many hours. Days really. I hate waste. Especially if it is a quality natural product. I bit the bullet and just tossed it. Wasn't that blue a lovely accent colour.