>>96993616it's fucking sick. This happens because when the bismuth goes from liquid to a solid is freezes by following a crystal structure that creates the square shapes. The colors happen because once it's solid there's a layer of oxide that forms on the surface and the thickness of the surface affects the color, and the thickness varies depending on how quickly it freezes, so it creates those cool patterns.
It's the same kind of thing that makes titanium oxides all colorful.
