What is the worth of a large copper Declaration of Independence Commemorative Mint coin with a registration number on it? It shows portions of four of the signers of the Declaration of Independence on one side partially encircled on the edges of the front coin with stars, and on the other side is the American Eagle holding two American Flags, one with the original 13 stars in a circle and the second flag perhaps reflecting the flag as it appears in the 1976 bicentennial year? The number on the eagle side flanked by the poles supporting the flags above the eagle shows: registration number 502417. Beneath the registration number is The Commemorative Mint, P.O. Box 8, Providence, RI, with a ZIP code that appears to be 02901. What is the value?