I haven't dropped any large amounts of powder, yet. But I bought a pound of IMR 4895 that a customer had opened and dropped in the store. The clerk used a business card to scrape t up and with it came the dust normally on the floor. I got 3/4 lb for $5.00 and I've used it just like a "clean" batch and can't tell any difference from the added dust (chronoed the same).