I found an old sterling silver ring, and can't find out where it might be from?

Just today i found a sterling silver ring with what appears to be a large oval black agate stone and a german eagle on each side. From the looks of it, the ring apears to be worn on the inside and very old. I dont want to take it to a shop and get scammed if it has any sort of value to it. Can anybo/dy offer any advice to what it might be worth or a website where i can find any legitimacy to its value?