My neighbor(5miles west of me) owns 80 acres and was digging a hole in her back yard so she could plant a bush. The hole was about 14 inches deep as the black sand is about 15 inches deep then you hit hard pack. While digging she hit something. At first she thought it was a rock but retrieved it from her shovel and it was this strange coin. Mind you, this is in the middle of the eastern Oregon desert. The coin looks like some type of hammered roman coin to me. The material is not silver more like pewter. It is fairly light material and the coin is in excellent condition for being buried in the magnetic sand. I am not familiar with these types of coins. HELP! what is it and is it valuable? I will attach photos.