Clad with gray Aswan granite, it is engraved with letters and graphic inscriptions of cultures and societies around the world.
No engravings were ever made onto it, as it was not allowed. 
mnli hypothesis: No engravings were ever made onto it, as it was not allowed.  premise: Clad with gray Aswan granite, it is engraved with letters and graphic inscriptions of cultures and societies around the world.