The usual advice when someone suggests cleaning a coin is to say NO, NEVER! because cleaning destroys a coin's collectible value.
But 1967 Kennedy halves are valuable only for the small amount (40%) of silver they contain, so if you want to use a product like Tarn-X or similar, you won't harm its metal value. The coins are still common among collectors so the chances that you could sell it for more than its metal value are extremely low.
Not all silver. It is referred to as silver clad. Silver on both sides (40% by weight) with copper in the center. The semi-solid silver Kennedy half dollar stopped production in 1964, made of 90% silver. See the related link for more information.
Gus Grissom died in the fire at the Apollo spacecraft in 1n 1967.
The Apollo 11 spacecraft was built between 1967 and 1969. It was specifically assembled at the Kennedy Space Center in Florida.
Apollo 1 was on Pad 34, Cape Kennedy, or as it's now known Launch Complex 34, Cape Canaveral.
10 January 1967 was a Tuesday.
Merle Kennedy was born in 1967.
Ambrose Kennedy died in 1967.
Simon Kennedy was born in 1967.
Margaret Kennedy died in 1967.
Emma Kennedy was born on May 28, 1967.
Emma Kennedy was born on May 28, 1967.
Duncan Kennedy - luger - was born in 1967.
The Kennedy Dream was created on 1967-02-16.
Clean Sweep - 1967 was released on: USA: June 1967
Caroline Kennedy-McCracken was born in 1967.
The Bobby Kennedy law of 1967 is also known as The Postal Revenue and Salary Act of 1967, it states that the President can not appoint relatives to paid executive positions.
Patrick J. Kennedy was born on July 14, 1967.