Although the volcano has experienced relatively little dissection, the western cone has been eroded to the base. Post-volcanic erosion has created an apron of rock fragments at Koh-i-Sultan's base, with radially incised valleys bearing traces of energetic stream erosion emanating from the volcanic cones. Koh-i-Sultan's remaining rock formations often have irregular shapes with a striking appearance; a 1909 report noted the presence of a monolith-shaped rock and a dome-shaped rock formation, Koh-i-Kansuri. Neza e Sultan (Sultan's Spear) is a major spear-shaped rock formation, about high with a basal diameter of . Weathering has created longitudinal fissures in the rock. Similar pillars are found elsewhere on the volcano, reminding early explorers of Gothic architecture and minarets. Neza e Sultan (possibly named after the mythical Sultan-i-Pir-Khaisar, who is reportedly buried nearby), at the westernmost crater, was discovered by Europeans in 1877. The rock formations may be necks of old volcanic centres. Gravel, pebbles and sand form playas and dunes, also found in dry valleys.