Carolus Iii
Where do I find information about rare coins?
1783 European Carolus III DEI GRATIA
Your coin is Spanish colonial (Carlos III was king of Spain in 1783).
On the side opposite the portrait at about the 10 or 11 O’clock position, there is a sequence of letters that comprise the mint mark, denomination, and the mint master’s initials (For example, Mo 8R FF would be an 8 reales coin from Mexico City mint with mint master FF).
This type coin was also minted in San Luis Potosi (Bolivia) and Lima (Peru), as well as other South American mints. The mint mark will tell you which one.
Here is an example of one that is presently for sale on eBay:
http://cgi.ebay.com/1783-Spanish-Milled-Silver-Dollar-Coin-w-COA-MUST-SEE_W0QQitemZ250038005720QQihZ015QQcategoryZ39481QQssPageNameZWDVWQQrdZ1QQcmdZViewItem?hash=item250038005720
http://pictures.kyozou.com/pictures/_2/1469/1468640.jpg
Carolus III Half-Reale: May 2011