I have a 1000 Franc Gold Casino chip from Monte Carlo. It was produced in 1979 to commemorate its 100-year anniversary. It is 15.5 grams of .500 gold and is 32mm in diameter. It is in brilliant uncirculated condition in its original box. It is a real chip and can be wagered or redeemed at the Casino. The original issue price was $290.00 US. I’m interested in determining a value for it for sale; can anyone help me?