What is Prince Rupert's drop?

One of the most fascinating examples of glass making is the 'Prince Ruperts drop' also known as Dutch or Batavian tears. These drops are made by dropping molten glass into very cold water which forms a comet or 'Tadpole' like shaped drop. These drops have some amazing properties not often found in other examples of glass or any other material. See the Wikipedia link below or watch the educational videos for a lowdown on this mysterious form of glassware.

https://en.wikipedia.org/wiki/Prince_Rupert%27s_drop