This is a very collectable Limited Issue, 1828 George IV Re-strike Shield Gold Proof Full Sovereign Coin Minted by the Pobjoy Mint.
The coin is hallmarked solid 22 Carat Gold in a Proof Finish and is a very Limited Issue of only 100 coins Worldwide.
These solid 22 Carat Gold coins have been struck to proof quality using specially prepared dies and highly polished blanks.