Here are some ideas I put together in about 10 minutes.
First, in PS I copied the layer with the pic about 4 times:
1. Select the stone area with select>color range, then select>inverse & delete all, so the stone is all that remains. Then Filter>Texture>Texturizer on the sandstone settings. Play with it until it looks like stone. Set the opacity of this layer down to about 30%
2. In the next layer do the same as above so only stone remains, then Layer>Layer Style>Bevel and Emboss. Do the bevel & emboss with an inner bevel (play with settings). Also click the Contour box & play with those settings.
3. Create one last stone ring layer--place it on top of all others--and run Filter>Texture>Grain on the enlarged type, & play with settings. Put layer blending mode to overlay & play with opacity.
4. Select>color range on the water now, then inverse that & delete, so only water remains. Then inverse & add a shadow with a hard-edged black brush set at about 10 % opacity. Finally, Filter>Distort>Ocean Ripple (play with settings).
Now, when it all looks good to you, Layer>Merge Visible. Then Filter>Blur>Gaussian Blur to about 4 px or so--just to take the hard edge off.
You can also play with Image>Adjustment settings like Hue & Saturation, Brightness, etc.
I copied the layer one last time, set the layer on top to Overlay blending mode and 50% opacity, and ran the Filter>Render>Emboss on it & played with the settings.
I also played with the Filter>Render>Lighting Effects to put a spotlight on it & played with settings.
That's it! If I were to mess with it more, I'd eliminate the black surrounding and add a floor with more shadow & depth, and maybe some details like rock on the floor, etc. I'd also add some sort of bottom or depth to the water so it's not plain blue---but good enough for now! I hope this at least sparks ideas!