Answer:
A certain wizard resided in a city made from this gemstone.
I have rivers without water. Forests without trees. Mountains without rocks. Towns without houses.
I grow for a surface, even if you cut me. I continue to grow even after death.
What goes through a door but never goes in. And never comes out?
Born of earth, but with none of its strength. Molded by flame, but with none of its power. Shaped
What covers its face with its hands, speaks no language, yet most known what it's saying?