Aluminium Powder: Molten Aluminium Shot into Water, then Stamped

Aluminium powder is the fuel of the thermit reaction that turns metal oxides into metal. Thorpe (1912) gives how it was made: molten aluminium poured into water, and the small irregular fragments, once dry, pounded under stamp-mills until fine enough. Molten metal and water: face shield, gloves, and pour slowly. Keep the powder away from flame. The picture: aluminium powder (Wikimedia Commons).