Admiral Vernon was a hero to American Colonists because he defeated the Spanish in a series of navel engagements in the early 1700s. In fact George Washington's' older brother served on one of the ships of the Admirals fleet. So much a hero, George Washington named his Estate, Mount Vernon, after the good Admiral. That is why this series of medals, of which there are many, are so collectable among Collectors of Colonial Era Coins. Enjoy collecting!!
Nice piece! I was interested so I looked it up. Here's a little information on the medal... http://www.coins-of-panama.com/vernon/vn4-62.html?Size=SmallNOen