From the pictures, I was skeptical that the coin was indeed a proof coin, so I did a little research. My feeling was that it was one of those business strike "S" coins produced not for circulation, and only available for sale at the US Mint. I was wrong, as the mint started to produce business strike "S" in 2012...... https://www.coinworld.com/news/us-coins/s-mint-quarters-from-us-mint-bring-premiums.html
