Some factors that can affect the value of a 1942 walking liberty half dollar include:
* Mint mark: The mint mark of a 1942 walking liberty half dollar indicates where it was minted. The most common mint mark for this coin is the "P" mint mark, which indicates that it was minted in Philadelphia. However, there are also "D" mint marks, which indicate that the coin was minted in Denver, and "S" mint marks, which indicate that the coin was minted in San Francisco. The "D" and "S" mint mark varieties of the 1942 walking liberty half dollar are generally more valuable than the "P" mint mark variety.
* Condition: The condition of a 1942 walking liberty half dollar can also have a significant impact on its value. Coins that are well-preserved and have few or no scratches or blemishes are generally worth more than coins that are worn or damaged.
* Grade: The grade of a 1942 walking liberty half dollar is determined by a professional coin grading service, such as the Numismatic Guaranty Corporation (NGC) or the Professional Coin Grading Service (PCGS). Coins that are graded as "Mint State" or "Proof" are generally worth more than coins that are graded as "Circulated."
If you have a 1942 walking liberty half dollar, it is worth getting it appraised by a professional coin dealer or coin grading service to determine its value.