Kial said that a team of geologists has begun studies to shed light on
part of the industry, art, and culture of the Achaemenid era.
mines of the white and azure stones used in the complex have already been
identified by experts, and when the black stone mines are discovered, the
project will be completed,” he said.
the identification of the original location of the black stone mines,
experts will be able to learn about the methods of stone extraction used
in ancient times, and (these sites) could be a good source (for materials)
for additional renovations of the complex.
studies on the stone structures of the Achaemenid era indicate that the
experts of those years used to make several holes in a part of a large
rock and placed pieces of wood inside the holes. They later ran water into
the holes, which helped them remove the piece from the rock,” he noted.