The only "strange marking" is the designer's monogram, a stylized G R, for Gilroy Roberts.
All circulation halves minted since 1971 are made of the same cupronickel alloy "sandwich" as dimes and quarters. They are only worth face value. Since 1992 special collector editions have been struck in 90% silver. They cost MUCH more than 50¢ each, of course!
The US Mint did not produce any half dollar coins in 1922.
You don't.
The 1966 Kennedy half dollar is made of 40% silver and 60% copper. It has a total weight of 11.5 grams and a diameter of 30.6 mm.
It's either not JFK or not a dollar. JFK is on the half dollar. President Eisenhower was on the dollar in 1972. Regardless, it's made of the same material as all other clad coins. It has outer layers of 25% nickel and 75% copper bonded to a core of 100% copper. If you have one in circulated condition, it is only worth face value.
About one dollar.
If you mean a 1971-D half dollar, it's just 50 cents.
A 1971 Kennedy half dollar is worth anywhere from $45 to $280 dollars. The Kennedy half dollar began circulation in 1964.
It's just a common half dollar no silver spend it
50 cents.
.50
50 cents.
Copper-nickel clad "sandwich" metal, the same as dimes and quarters.
All copper clad U.S. half dollars dated 1971-present weigh 11.34 grams.
50 cents.
50 cents.
50 cents.