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For the new collector, a coin price guide can be a little overwhelming. They are loaded with abbreviations and special terms and column after column of numbers. However, learning your way around these guides can increase your appreciation of some of the hobby's subtleties and begin your education about how coins are valued. As you advance in your collecting and begin to invest in more expensive coins these understandings will undoubtedly save you money.
Unless stated otherwise, you should assume that a coin price guide is referring to retail values. In other words the price that you might expect to pay a dealer -- not the price that a dealer would pay you if you were to sell. When selling coins to a dealer you must allow a margin for profit. However, when selling to another collector you might hope to realize something somewhat closer to these retail values.
A typical coin guide will provide an individual section or table for each coin type. Better guides will provide some basic information at this point including the period during which the coin was minted, metal composition, and characteristics unique to the series that will help in identification.
Collectors of United States coins distinguish coins by the year of issue and by the mint where the coins were struck. In modern times these mints are indicated by a letter known as a mint mark somewhere in the design - D for Denver or S for San Francisco. If there is no letter the mint is Philadelphia. In addition to the mint varieties, price guides will often list other commonly pursued varieties. DD, for example, is a well known abbreviation for double die a term which refers to coins accidentally struck twice featuring a shadow impression.
Any decent guide will list values in multiple grades. Coin collectors assign a grade to coins based on a number of factors, mostly related to the amount of wear on the coin. These grades are generally abbreviated - G for good, F for fine, EF for extra fine, and so on. The guide should define the grades that it uses. You will often see numbers associated with grades, as in "G-4" or "MS-65.". These numbers refer to grading standards that have been published by the American Numismatic Association and are often associated with professional grading services which, for a fee, will certify the grade of a coin.