There is no marking but history tells us this is 10 karat gold filled. It has a nice weight to it and was possibly manufactured as a watch fob given it's weight but works just as well as a charm.
It weighs 7.5 grams and is approximately 3/4" in diameter.
Marked with Reach's slogan "The Sign of Quality" along with logo. There are some initials on one side. The first row is unreadable with certainty but we believe it is Ret'd (for retired). The second row is R.O.T.C.. These letters are seen on close inspection.