MENU marble shelf :

https://menuspace.com/collections/storage-shelving/products/plinth-shelf-marble 

each shelf has : H : 10 cm - W: 60 cm - D:12 cm

“Who works with V-Ray version lower than 3.1, pay attention to materials section BRDF (Microfaset GTR (GGX)), if your version is older than 3.1 - this section will be empty, and you have to choose: Blinn, Ward or Phong, d dependence on material “.