Sure, no problem. Find the adjusted material attached. – The trick with the translucent material mixed with the principled shader is not really neccessary. I would simply use SubsurfaceScattering for this, unless you want to make a rendering, where the snailhouse is actually lit completely through from the back? – You could even skip that completely for faster rendering depending on the lighting of the final scene.
A bit of explanation of the nodes
- The math node is not really neccessary, but I used it for illustration purposes here. The larger the SSS radius, the more area the light shining through the object will affect. – I put a purple light into the shell for testing.
- I used an RGB Curves node to modify the diffuse texture for the SSS color. By giving it more contrast, dark parts of the shell will appear darker and light parts lighter, when light is shining through the object. The Hue/Saturation after that is used to take the amount of color added by the contrast down a bit.
- Another RGB Curves node is used to tone down the diffuse map using it for the specular (reflection amount) and specular tint (reflection color) input. You could split this into one RGB curve for each input for better control over reflectivity and color, or use the displacement map for the specular input instead. But it seemed to work out that way, so I kept it simple here.
- The input to the roughness value runs through a color ramp node. A white value would make the material completely rough, a black value would make a completely clear reflection. That´s why the light/dark values are reversed, so that the higher parts of the displacement will be more reflective. By adjusting the grey values in the color ramp the glossiness can be changed.
I hope that helps? – Curious to see the snail you are going to put in there?