To create this model, I was guided by the data of the technical requirements for the classic diamond cutting. Parameters of a single stone : vertexes-90, edges-180, faces-92. Faces without distortion. The materials and scene are saved. The model was created in Blender 2.82.7. Also exported to formats .obj, .fbx If you want to take one stone from the scene and need to translate it to zero coordinates - import it from the file .blend to your blend file and just change the position and rotation coordinates to 0. If you are not satisfied with anything in this model, you can write to me and I will try to help you.