Collectors can buy this coin on the Mint's site, but it won't be cheap. It has a mintage of 7,500 and is being sold for ...

The most famous packing problem concerns spheres. In 1611, the astronomer Johannes Kepler proposed that the densest way to ...

Calling all bee lovers with money to spend — Canada has a new buzzing honeycomb-shaped coin. The Royal Canadian Mint released ...