What is the value of a 2 and a half dollar gold coin?
$2.50 gold coins were struck from 1796 to 1929 at about a half dozen mints so you have to be MUCH more specific.
Please post a new question with the coin's date, how worn it is, and whether you can find a small mint mark on the back side, usually under the eagle.
Gold plating adds no value when it comes to coins and indeed is a form of damage. A gold plated coin is worth the same as a damaged example of that coin. For example, a gold plated 1964 half dollar is worth the $7 in melt that a normal damaged 1964 half dollar is worth. A gold plated 1971 half dollar is worth 50 cents just like a damaged 1971 half dollar is worth.
Your coin is an ordinary copper-nickel half dollar with a portrait of President Kennedy. It's not gold, just gold-plated. The plating was added by a private company that sold the coin as a "collectible" but it has no real value beyond 50¢ except as a curiosity. Coin collectors consider it to be an altered or damaged piece; in any case it would cost more to remove the gold plating than its value as a precious…
July 3, 2009 The 1977 Kennedy Half Dollar in uncirculated condition is worth about $3. There may be a few cents additional value for the gold plated on it depending on the purity and thickness of the plating. As far as a collectable value, there is some interest in collecting gold plated coins but from a numismatic view the half dollar is not as issued by the mint and by plating it, even with gold…
Assuming the coin is circulated and has no "S" mintmark, retail value is $490.00-$560.00 depending on the actual grade of the coin. 1899 Liberty Head Half Eagles are a high mintage, very common date gold coin. NOTE: If the coin has been used as a jewelry piece, or cleaned, value is for the gold content only.