Strange coins

[pickinduck]

I was just reading this article about this rare penny that went to auction and sold for a lot of money but that is not what fascinated me most. Its the other coins in the article that really caught my attention.

news.yahoo.com/blogs/sideshow/1-million-penny-one-world-rarest-coins-sold-181733038.html

What is a glow-in-the-dark quarter made of?
How do they shrink a quarter magnetically?

[pickinduck]

Glow-in-the-dark quarter.

news.yahoo.com/blogs/sideshow/canada-issues-glow-dark-dinosaur-quarter-173052860.html

[pickinduck]

Shrunken quarter.

www.thinkgeek.com/geektoys/science/ecfb/?pfm=rightcolumn_NewStuffFTW_11

[sherlew (Ret)]

Neat stuff. I didn't know that coins used to be made with a silver plug in the middle. It's probably worth picking up the glow in the dark Canadian coin, too.

[pickinduck]

Those Electromagnetically Shrunken Quarters captivate me.
Does it work with any metal?
Does it change the property of the metal and if so how?

[pickinduck]

[pickinduck]

It appears to me that it uniformly compresses the coin a long a single plane.

[sherlew (Ret)]

Looks like it. Also it appears that some metals compress better than others.