The provided context is insufficient for answering the question, as it consists of a non-functional link and generic website footer information. Therefore, this answer is based on general numismatic knowledge.
The premise of your question contains a common point of confusion. The majority of 1972 Kennedy half dollars are not made of silver and, as a result, are typically worth only their face value of 50 cents. Beginning in 1971, the U.S. Mint ceased using silver for circulating half dollars and switched to a copper-nickel clad composition. These coins, minted in Philadelphia (no mint mark) and Denver ("D" mint mark), were produced in large quantities and are common in circulation. In heavily worn condition, their value does not exceed 50 cents, though uncirculated examples may be worth a few dollars to a collector.
However, the U.S. Mint did produce a special collector's version of the 1972 half dollar that does contain silver. These coins were struck at the San Francisco Mint and bear an "S" mint mark on the obverse, below President Kennedy's portrait. These 1972-S half dollars were not intended for circulation and were sold to collectors in Proof and Uncirculated Mint Sets. They are composed of 40% silver.
The value of a 1972-S silver half dollar is primarily determined by its intrinsic metal value, often called its "melt value," which fluctuates with the market price of silver. This value is typically several dollars. In addition to its silver content, a small numismatic premium may exist depending on the coin's condition, particularly for those in high-grade proof condition. To determine if you have a silver version, look for the "S" mint mark and check the edge of the coin; the 40% silver coin has a solid silver-colored edge, whereas the common copper-nickel version has a visible copper-colored stripe.
