If you plan on buying or selling coins in the marketplace, get to know the various grading tags that are attached to them and what the labels mean. The coin's grade, along with its scarcity and demand, is a key determinant in its value:

• Proof: Although the term proof refers to a method of manufacture, the term does double duty in describing a coin in its impeccable mint state.

• Mint state: A coin in mint state shows no trace of wear.

• Uncirculated: An uncirculated coin is nearly perfect, exhibiting no trace of wear, except perhaps some contact marks, surface spots, and diminished luster.

• Extra fine: an extra fine coin has sharp features overall, but the design of the coin is lightly worn with diminished luster.

• Very fine: The features of very fine coins are still sharp and well detailed, but the coins have moderate wear on the high points of the design, as well as diminished luster.

• Fine: The features of fine coins are still sharp and well detailed, but there is moderate to considerable wear throughout the coin's design, as well as diminished luster.

• Very good: The features of very good coins are still clear, but the coins are well worn and look flat.

• Good: The features of good coins are still visible, but they are faint in spots, and many of the coins' details are flat.

• Fair: A fair coin has very heavy wear, with portions of the coin's design worn smooth and parts of coin possibly even unreadable.