Congrats, that's a rare treat! I've found the occasional silver dime in my change, but never a quarter.
I'm amazed by how so many people I've spoken to have no idea about silver coins, or how to tell which ones they are. I've heard "coins used to be made of real silver?" and "so what, what's special about that?" and "are they worth more or something?" and "ooh, I have silver polish!". Lol