* Condition: The condition of a coin is one of the most important factors in determining its value. Coins that are in mint condition (MS-65 or higher) are worth more than coins that are circulated or damaged.
* Variety: There are several different varieties of 1964 US quarters, each with its own unique characteristics. Some of the most valuable varieties include the 1964 Proof quarter, the 1964-D Special Mint Set quarter, and the 1964 SMS (Specimen Strike) quarter.
* Strike: The strike of a coin is another important factor in determining its value. Coins with a strong strike (sharp details and well-defined features) are worth more than coins with a weak strike.
* Luster: The luster of a coin is the way that light reflects off of its surface. Coins with a bright, reflective luster are worth more than coins with a dull or milky luster.
* Eye appeal: The overall eye appeal of a coin is also important in determining its value. Coins that are visually appealing (with few or no scratches or blemishes) are worth more than coins that are unattractive.
In general, a 1964 US quarter in good condition is worth around $1.00. However, a 1964 Proof quarter can be worth up to $100, and a 1964-D Special Mint Set quarter can be worth up to $500. If you have a 1964 US quarter, it is worth having it evaluated by a professional coin dealer to determine its exact value.