Bathroom set with onyx sink with lighting

Onyx material:
It is important that Volumetric scattering is selected in the mode window in Volumetric and SSS. Otherwise, the transparency parameters will be inactive.

In order for the material to look correct on the render, a light source is needed in the onyx sink. In the scene, this is the CoronaLight mtl material. If you want to make a shot without backlighting, you need to apply a regular stone material with a stone texture from diffuse to the wall.

Glowing from within onyx sink
Self-luminous stone

Corona version 10
CoronaLegacyMtl Materials
In CoronaRender 6 and below CoronaLegacyMtl=CoronaMtl
CoronaLegacyMtl requires Corona Renderer version 1.5 or higher