Part of practice of issuing commemorative coins is the issuance of coin proofs or early samples of the coins which are minted to regularly check the dies used in subsequent minting of the coins themselves. This is also done for circulated monetized coins and if they are issued to the public can command collector’s item prices in the market after a few years.
These coin proofs are valued for their sharper coin designs and rims as well as smoother mirror-finished blank areas. Coin proofs form a special category of uncirculated mint coins that are often sold at a premium to coin collectors. Not all coins in circulation have been issued with coin proofs at the start but it is not uncommon for the US government to issue a set containing samples of each coin in circulated in coin-proof grade quality.
The US Mint strikes coin proofs such as Prestige Proofs of commemorative coins sold at a higher premium between the years 1983 and 1997. The issuance of proofs resumed in 2005 and they are now called Legacy Proofs that come in sets of a dollars, quarters and cents. In 2009, a proof set was issued containing 18 coins marking the Lincoln Bicentennial.
Starting in 1992, coin proofs for legal tender coins were issued in silver and other base metals. But US commemorative coin proofs are issued in bullion platinum, gold and silver. Bullion represents the highest purity of 99.999%. A bullion gold coin is essentially a 24 kt gold in jewelry terms and carries the highest market value.
| Coin auctions on eBay |
 1960 SILVER PROOF SET FRANKLIN HALF DOLLAR QUARTER US $24.99 |
 1951 Proof Set US $490.00 |
 1953 Proof Set US $190.00 |
 1971 S UNITED STATES PROOF SET IN BLUE BOX HOLDER US $4.95 |
 LOT OF 16 PROOF AND UNCIRCULATED SETS US $75.00 |
 1982 S UNITED STATES PROOF SET IN BLACK BOX HOLDER US $4.95 |
 2001 US SILVER PROOF SET w/STATE QUARTERS BOX&COA US $71.00 |
 1999 Proof Set US $18.95 |
 1957 Mint Proof 3 Sets US $79.00 |
 2008 Proof Set All Original US $53.50 |
