Navajo Ring Double braided shank and strange hallmark

I believe the turquoise to be cerillos, and it is Navajo. But past that I am not sure. It came from mom’s estate, may be 30 or more years old. I am not sure how to embed pictures on here. The hallmark seems to have been made by tapping lightly on a chisel type tool.
This is not a great one. but it shows shank and hallmark. http://i927.photobucket.com/albums/ad118/charlyb777/greenringbackandhallmark.jpg This one is the front. My drive crashed and I am busy finding all my pics.

Hello, thanks for sharing. None of us know this mark, and could not find it in any of our resources. The turquoise could be Cerillos, but it does look like two different mines.