It's so nice that the mirror actually held up sturdily throughout those years, and is still in a good shape.
The metal frame looks cool and silvery, but it's most likely steel and/or aluminum.
Personally, I'd try to find out with a small drop of Hydrochloric Acid somewhere unnoticeable on it qnd see how it reacts, just out of curiosity to rule out that it might be actually silver, but that's just crazy me π
In any case, for a mere $3 that's a nice find!
RE: My thrift store find for the Secondhand Finds Community contest