Arkose

The Rock Picture gallery has a new specimen: arkose. I had the choice of taking this on the plane from Denver or a piece of uranium ore, but I thought, "Which of these needs to be in the Rocks gallery?" and the answer was clear. It's a piece of the same stuff you see at the Red Rocks Amphitheater—300-million-year-old arkose from the Fountain Formation.

_{Arkose — Geology Guide photo}