When you drop molten glass in water, you end up with a glass structure that is extremely hard at the bulbous base but can be fractured easily at its tail. This is known as a Prince Rupert's drop.
However, this youtube video seems to demonstrate that dripping molten glass into liquid nitrogen produces a drop that can withstand the tail end being clipped off. I know of no situation where a Prince Rupert's drop wouldn't shatter if the tail was clipped, so dropping molten glass into liquid nitrogen does not produce a Prince Rupert's drop. Why not? If the temperature is a factor, then what is the temperature differentiation that determines whether or not a Prince Rupert's drop is produced? If one dropped molten glass into a liquid that was just 50 degrees C less than the glass, then would you end up with a Prince Rupert's drop? I'm assuming that relative temperature is the determining factor here, but I don't know. Is there something else that I'm missing? If it's a Leidenfrost effect then why doesn't it apply to both water and liquid nitrogen?
Can anyone give a reasonable explanation?