a gold coin
it depends what the year is and what the grade of the coin is.
500 dollars
The gold coin you are talking about is a "Centenario" and it is worth about $1,200 dollars (or 785 Euros).
A 1848 five dollar coin is worth about 1,600 dollars to about 2,100 dollars. A 1848 five dollar coin has been auctioned for over 71,000 dollars.
The Sacagawea, Presidential, and Native American Dollar coins all use the same type of planchet and these coins are worth anywhere from twelve dollars to fifteen dollars.
There are three different types of gold American Eagles coins. The one ounce coin costs fifty dollars. The quarter-ounce coin costs ten dollars, and the tenth-ounce coin costs five dollars.
eagle
About $2.00
It is worth 1 troy ounce of gold, which at the time of writing is $1,380.80 but gold prices are volatile and change daily. The condition of the coin if in absolutely pristine condition it can increase the value by twenty or thirty dollars or so.
If you mean one of the Sacagawea dollars or a Presidential dollar the date is on the edge of the coin and its not gold.
I've seen them as low as 25 dollars.