Cool stuff: Prince Rupert's Drops

Prince Rupert’s Drops

Just saw these on Very cool little things. You can read up on Prince Rupert’s Drops at Wikipedia, but the basic idea is this: Drop molten glass into a cold bucket of water. A tadpole-shaped piece of glass is formed in a way that produces a huge amount of tension within the glass. On the big tadpole end, you can hit it with a hammer, and unlike ordinary glass it won’t break. (Due to the high tension and the egg-like shape distributing the force.) However, if you even scratch the tiny tadpole tail, the entire thing explodes into tiny little shards, almost instantly. (The exploding front propagates down the tail toward the head at ~4200 mph = Mach 5.5)

Even if you didn’t read the above paragraph and/or didn’t care, check out this video of Prince Rupert’s Drops exploding from It’s awesome.

3 thoughts on “Cool stuff: Prince Rupert's Drops

  1. Timmo Dugdale

    While I was intrigued by your posting, the video left something to be desired. Thanks, though, for keeping my informed on the latest news in the glass-breaking world.

    Your friend,


  2. Colin M

    lol. As far as the Enlight thing goes, I think you’re pretty much a member if you want to be. I don’t know as though we even have a list anywhere, except maybe the mailing list. We can add you to that if you’re interested.

    As far as the Prince Rupert’s Drops, you might have some success with the method in the video, if that kind of equipment is available in the glass lab, or you can also try this site: Prince Rupert’s Drops Lab, though according to that one, the success rate is pretty low at actually forming them. If you do try, let me know how it goes, or bring one to Enlight some night. without scratching it, obviously 😉


Leave a Reply

Your email address will not be published. Required fields are marked *