Actually this concept is easy to understand but we must first look up the word numismatic. You will find it is the study or collecting of coins or paper money. If you study, collect or invest in coins then you are a numismatist. This definition worked for years and thus was used by the American Numismatic Association. But when our money supply began to inflate many people looked at gold and rare coins as a way to protect their wealth. A generally good idea to protect purchasing power from any government that does not wish to balance its books.

With so many people seriously considering coin investment the coin industry thought a few more descriptive terms were necessary to help the process.

If the price of your coin was substantially above the melt value then it was called a numismatic or rare coin. An example is the MS-65 Saint Gaudens gold piece which sells for perhaps three times its gold weight. It contains about an ounce of gold so the difference is of course the rarity factor. The same $20 in circulated condition is more common, but still worth a premium.

The circulated $20 gold piece, while scarce, is not nearly as rare as the same coin in PCGS MS-65 condition so the trade needed a term that would more adequately describe the more common coin, for they did not feel it warranted the term "rare". Still it was not a bullion coin because it did not trade for close to its weight. Thus the term "semi-numismatic coin" came into general use.

Semi-numismatic coins have a large following. Circulated $20 and $10 gold pieces are popular because they trade at premiums large enough to make them exempt from confiscation but low enough to make most bullion buyers happy.

The most quoted semi-numismatic gold is the $20 Liberty in Very Fine (VF), Extra Fine (EF) and Almost Uncirculated (AU). Because the difference in the cost of these grades is small, the investor is better served with AU coins. These are not rare coins, thus PCGS grading is not required.