John J. writes: I have a 1980 (nineteen-eighty) Washington quarter struck on a 90% Silver planchet. Do you know if any others exsist?,and what possible value would it have. I grade the coin AU50 or 53. I curently have it in my BU collection of Wash. Qtrs. 1932 to present. I have not sent it in for grading and authentication. Thanking you in advance, John
No 1980 Philadelphia quarters have been reported struck on 90% silver planchets. In order for that to happen 90% strip would have had to exist at the mint in 1980. Rolls of prefabricated metal of the proper thickness and material are run through a machine that punches out planchets of the proper size. Since no 90% silver strip was available at the Mint in 1980 it would be difficult to create 90% silver quarters. If such an error occurred there would be thousands of silver 1980 quarters in circulation.
I’m do not know what method you used to determine that the coin was struck on a 90% silver planchet but there is an easy way to tell. There is a substantial difference in weight between a copper-nickel clad quarter and a silver one.
- Copper-nickel clad quarters weigh 5.67 grams
- 90% silver quarters weigh 6.25 grams
40% silver quarters were struck for the Bicentennial in 1976 but only in San Francisco ( “S” mint mark). These coins have a special design and show the dual date “1776-1976”. The production of 1976-S 40% silver quarters continued for several years. 40% silver quarter planchets weigh 5.75 grams. (Note that San Francisco copper-nickel clad proofs also exist.)
If the weights indicate that you have a 90% or 40% silver quarter, it would be currently, the only one known with the date 1980 and I imagine it would be quite valuable. If the weight checks out, you should have the coin certified by a third party grading service such as NGC or PCGS. See their links on the CoinSite Links Page.