I have this quarter that is very shiny. Its pictured below on the right... the quarter doesn't work in vending machines. I weighed them on an analytical micro-balance... and the 1998 quarter pictured on the left weighed in at 5.75192g and the shiny quarter is 5.61926g. The quarter seems to be a little thicker and the copper appears to be much thicker than the other quarters I have. I tried to get a on edge picture but it may not have turned out very well. I had meant to measure the coins with calipers but forgot to. Also, the ridges around the coin seem to be more "aggressive" and more rough that the other quarters I have. The S stamped on the face side is not super clear and I had to use a magnifying glass to be able to determine that it was indeed an S. I am thinking the 1979 S shiny quarter is a counterfeit piece, but wanted to ask the community before I turn it in.
That's what it is. Proof coins are issued by the mint for collectors. They aren't meant for routine business. The edges feel extra sharp to you because they are. They are not struck like regular business coins are struck. Put it in a holder and hang on to it. It is a nice find.
I have found 2 proofs in circ in my life, one silver, and one clad. Nothing this old or gorgeous though! Good work!
