All Buffalo Nickels 1913-1938, Jefferson Nickels 2005, Kansas state quarter 2005, North Dakota state quarter 2006
The South Dakota double bison gold coin is a commemorative coin issued by the South Dakota State Historical Society. It features two bison on one side to symbolize the state's rich history and connection to the American West. The coin is made of gold and is a collectible item for coin enthusiasts.
Put a picture of the coin!
No US half dollar has a bison on it. The picture of a bison was used on US nickels. I think you mean BICENTENNIAL. If so, please see the Related Question.
Which coin did you have in mind?
The picture on the back of the Sacajawea coin is a young Shoshone woman. She has her infant son on her back in a wrap. This coin was a replacement for the Susan B. Anthony coin.
Your coin is a medallion probably rare. Where did you find the coin?
platapus
Sacajawea
The penny.
This would be very rare coin because the Bison reverse was only used on the Jefferson nickels in 2005 not 2008. Look at the coin again.
Pictures of a specific coin are difficult to come by. Usually you should be able to find one on eBay, but the picture is withdrawn after the coin is sold. The only Five Pound coin issued in 1981 was a "Proof in gold FDC" coin.
See link to Australian one-dollar coin