This is a piece of sleet that i had scraped from the very top of the ice pile on my BBQ pit cover...this piece had no other contact with anything but the ice beneith it. The slide i used was brand new and cleaned prior to placing the sample on it. What you in the beggining see are air bubbles from the ice melting on the slide... Jump to 1:46 and 3:00 if you want to see why i dont open my mouth for snow or rain from the sky! REMEMBER, THIS IS A PIECE OF SLEET ABOUT THE SIZE OF A PIN TIP.