If you have a strong magnet you may want to consider "stirring" the powder with that magnet attached to something. I had a bottle of Longshot that was contaminated with rust flakes in a brand new bottle purchased from Fin, Feather, and Fur in Ashland, Onio. As for how that could happen, it's my understanding that the bulk powder is shipped to Hodgdon in Railroad Cars and I suspect that if we were able to inspect those railroad cards we would find many are rusting. Good news for me was that my Neodymium Magnet pressed into the end of a brass rod did a fantastic job of picking up the rust flakes out of the powder.