This dome is also known as the Gabri Dome and is located at the eastern edge of Kerman. This is a mysterious, octagonal structure, which houses a museum of old gravestones. It is mysterious because its age and original function remain unknown. Some scholars date it to the 2nd century AD and think it may have been an observatory; others say it was a tomb. Whatever its function, it is remarkable because it is constructed of stone and gypsum rather than the usual brick; though the double-layered dome, added 150 years ago, is brick.
Jabaliyeh Domes' architectural affects have been inspired from the Sassanid period.

More photos of Kerman:
http://www.pbase.com/k_amj/kerman