Based on general numismatic knowledge, as the provided context was insufficient, the rarity of a 1979 dollar coin is not based on the standard issue but on specific minting varieties. It is a critical point of clarification that the 1979 Susan B. Anthony dollar is not a silver coin; it is composed of a copper-nickel clad, a factor that often leads to public misconception. The standard circulation strikes from the Philadelphia (P), Denver (D), and San Francisco (S) mints were produced in very large quantities and are exceedingly common, typically holding little to no value over their one-dollar face value unless in pristine, uncirculated condition.
The primary factor that makes a specific 1979 dollar rare is the "Wide Rim" or "Near Date" variety. This scarce variety was struck on a 1979-P (Philadelphia mint) coin using a modified die that was later intended for the 1980 proof coins. On this variety, the date is positioned significantly closer to the coin's rim, which itself is noticeably thicker and more pronounced than on the common "Narrow Rim" or "Far Date" version. This error occurred on a limited number of coins before being corrected, making the 1979-P Wide Rim dollar a sought-after collectible.
Additionally, while not as widely known as the Wide Rim circulation strike, there are two distinct varieties of the 1979-S proof coins. These are differentiated by the shape and clarity of the "S" mint mark. The Type 1 proof coin features a mint mark that appears somewhat bulbous or filled in, often referred to as a "blob S." Later in the production run, the mint utilized a new, clearer punch, resulting in the Type 2 proof coin, which has a much sharper and well-defined "S" mint mark. The Type 2 variety had a lower mintage and is considered scarcer and more valuable than its Type 1 counterpart. Therefore, the rarity of a 1979 dollar is determined by these specific die variations rather than the coin's date itself.
