Known as the Gunbad-i Alayvian, this structure is assumed to be a mausoleum; square on exterior and interior, with the dome no longer extant. The plan incorporates an unusual stellar flange that protrudes from each exterior corner, rising to a height lower than the main mass. The period of construction is contested, ranging from late twelfth century Seljuk to fourteenth century Mongol. Wilber proposes construction c.1315. Rich ornamentation covers the exterior; terracotta and stucco form inscriptions, and geometric and brick bonding patterns. The interior is plaster coated, with areas of carved stucco in high relief.
Sources:
Pope, Arthur Upham. "Architectural Ornament." In A Survey of Persian Art from Prehistoric Times to the Present, edited by Pope, Arthur Upham and Phyllis Ackerman (assistant editor), Vol. 3 Architecture, Its Ornament, City Plans, Gardens, 3rd ed., 1301-1302. Tehran: Soroush Press, 1977.
Wilber, Donald N. The Architecture of Islamic Iran. New York: Greenwood Press, 1969.