Silver ring with dark reddish brown stone- sz 10.5, 10 1/2

I genuinely thought this ring was silver, but it does not have an engraving on it anywhere. It has some tarnishing on it just like silver, but is a super cool ring, with a unique colored stone in it. The stone is shiny, and a dark red orange/red color. I suppose it could be considered a light brown? It has a unique setting, and is quite large. It is 3/4 long and 1/2" wide. It sits about 3/4" total off of your finger. It is a size 10.5. I've worn it a few times, and it has never left a mark on my finger, so really not sure what type of metal it is. It is not magnetic at all, which leads me to believe it might be silver. Again- it has no engraving of any numbers anywhere. It has a kind of Western look to it.