As with your Washington, DC Monuments piece, what you have here is a medal not a coin (i.e., no monetary value). Also as with your other piece, if it contains any precious metal it is very likely just a thin plating of silver over a base metal vs. a solid silver medal. It is a common piece with a value is in the range of $5-$10.
The design on the reverse is the Great Seal of the State of South Carolina; it is a common design element used on many tokens and medals related to South Carolina. You can read a full description and history of the Seal on wikipedia if you are interested.
@1188howest: Neither of your responses was accurate, please be careful when posting answers to questions when you're not certain of their validity. No collector wants to be misinformed when they are looking for help on one of their coins/medals/tokens, etc.
Collecting history one coin or medal at a time! (c) commems. All rights reserved.
Edited by commems
02/03/2013 12:00 pm