Willem, it's a very interesting coin. I assume it is in a 2x2 coin holder and therefore quite small. I could not find one like it anywhere on the Internet. I did notice something odd about it though compared to all the 100's that are out there. First, it says ROBERT then JOHN KENNEDY. Every other coin out there lists JOHN, then ROBERT. That is because JOHN was the President of the United States and ROBERT was the Attorney General (a lower post).
Also, every other coin out there shows JOHN'S face in the forefront with ROBERT behind. Your coin shows them opposite. The Reverse of the coin depicts the Presidential Seal which is confusing because once again ROBERT is listed and shown first on the obverse!
Is the coin actual gold or just gold colored? If it is actual gold it should be stamped somewhere with some sort of purity, i.e. .999 etc.
LATER: Willem, the picture is a little shiny but does the obverse say ROBERT e JOHN KENNEDY? If so, I'm thinking the coin is French made. An American made coin would say ROBERT AND JOHN or ROBERT & JOHN.