Keeping in line with the simplistic nature of the other coins on the market, this is the design I have come up with.

http://i120.photobucket.com/albums/o174/randi25_01/WorldCoin16x16_zpscafad469.png Here is the 16x16 size.

And here it is bigger.
http://i120.photobucket.com/albums/o174/randi25_01/WorldCoin_zps9050bc51.png