It's a Thai Buddhist medal. It depicts the 18 Arhats (also known as the 18 Luhan or Luohan), who are early Buddhist monks who have attained Nirvana but remain on Earth as protectors of Buddhism, awaiting the coming of Maitreya. Each Arhat has specific attributes he is usually shown with, which you can see in the picture.
A metal detecting buddy of mine found something very similar to that. Imagine the hole he had to dig to retrieve it....
It is Chinese coin. I believe it is called a "bee." That is a phonetic spelling. I puchased these in Bali, Indonesia. They were used in WW2 during Chinese occupation of the island.
