Issued by the US Mint in 1999, this was the last dollar coin minted in the 20th Century. The coin was available for purchase from the Mint from July 16, 1999, through July 15, 2000. 500,000 were authorized but apparently only 82,563 were produced.
These are US currency; not just ounce silver rounds, but real US Dollar coins
Design Theme on Obverse
The obverse shows a spouting geyser with the park's tree-lined landscape in the background.
Design Theme on Reverse
The reverse, adapted from the U.S. Department of Interior's seal, shows an American Buffalo on the plains with a sun rising above the mountains in the background.
These are all US Mint proof (unopened cases) and uncirculated coins. Content is 91% silver and 10% copper. Weigh is 26.73 grams.
Auction record for this coin was set in 2003 at $713.* Values fluctuate but currently between $80 and $550.