How can we show cove light effect on Black marble material.
I am trying but the material absorbs the light effect.
Sorry, but I don’t understand what you mean. Can you please explain. Maybe showing a real-life reference photo would help?
Onyx marble is translucent, esp. in veins.
Easiest solution would be self-illuminating map.
Using actual translucency/SSS means you have to model the planes realistically thin (1-2cm).