agate?

Found this doing spring cleaning at a place I bought so don't know for sure where it came from but would guess the Yellowstone river area. It's fist size with bright orange or red. Photo was taken wet to show the colors. Is it a blood agate? Any idea of worth? Thanks

My best guess is an agate forming around a bone The outside is hard but the white rock/substance that the rock seems to be forming over is soft