This is a Prince Rupert’s Drop or a Dutch Tear.
They’re volatile little buggers.
Prince Rupert’s drops are formed by super heated glass being dripped into ice cold water.
They start to solidify instantly and form an elongated teardrop shape with a number of unique properties. In particular stored tensile energy.
Viewed with polarized lenses the internal stresses become visible.
These rainbow patterns are caused by layers of glass that have cooled and contracted from the outside in, the inside is constantly pulling on the outside and everything is constantly pulling on everything near it. Because of these stresses, the “head” of them is insanely strong.
No really, they’re tough.
Direct blows from hammers have basically no effect on them.
Seriously, they’re tough.
Just look at that little glass sperm, just getting wailed on and it doesn’t even care. I bet it would make a strong glass baby.
However, the slightest tweaking of the tail will destroy them.
Explosively. That’s 30,000 frames per second.
At 100,000 frames per second, they’re like a really quick fuse.
A fuse of exploding glass. Safety goggles plz.
At 130,000 frames per second the explosion remains striking.
The failure front moves between 1.45 and 1.9 km per second, that’s 0.9 to 1.2 miles per second. That’s as fast as a really fast thing. This one is moving at 1658 meters per second according to the source video.
While they weren’t invented by Prince Rupert, he is thought to have brought them to Britain and popularized them.
They ended up being used as party favors in high society, basically glass shrapnel spewing firecrackers. Aristocrats were stupid.