It's a token made in the 60's to use in place of US halves on the tables and in the machines, Dan. Not particularly scarce. Commonly found in unused condition from the sets sold to collectors and Franklin Mint subscribers. There are used tokens out there as well. Value is from $2 to $10 depending on condition and which club issued them. I'm away from home, but I believe about 35 different casinos issued brass halves in 1967.

DonL