I take some metallic (white) tin, cool it off, and it converted to the grey allotrope. Arthur's video: https://www.youtube.com/watch?v=-IKOZGNHgjY Nile Red's video: https://www.youtube.com/watch?v=r-YbQN_twpw Help me make videos by donating here: https://www.patreon.com/CodysLab