its not clay its granite and diorite, some of the hardest materials to work with. the tolerances are extremely precise and extremely tight in these vases. and no you absolutely cant achieve this level of precision with your hands. literally impossible for you even in clay. and if you could you would do it in your backyard and then sell these vases as egyptian ones and make millions of dollars. but you cant because the fraud would be detected quickly. and even if you did it with professional tooling, you still wouldnt achieve this perfection on this level.
Germany