Spherical geometry in a voxelated phantom for grouping few voxels

Dear Experts,
I have a voxelated phantom. Now, I want to insert an spherical geometry using SPH card which will contain few voxels inside it. Is it possible ?
If yes, then I need to do the boolean operation as usual. That case, what will be assigned materials of the volume inside the sphere & outside the voxel ?

Alternatively, whether there is any way for grouping few voxels together ?
Any clue will be helpful for me.

Hi @ArghyaC

unfortunately with the VOXELS is not possible to perform boolean CSG operations, and it seems there is no easy solution for that at this moment. All possibilities I am thinking are complicated and require some programming.