The dramatic creamy textured rock in this part of Wadi Mijlas is Early Eocene limestone around 55 million years old. The rock includes thin beds of yellowish marly limestone and massive whitish nodular limestone. The rock is composed of calcite rich fossil sediments such as, bivalve, coral, Nummulites, alveolina and gastropod; showing its marine origin.
The remarkable structure of the rock is caused by karstification a process whereby water runs through fissures in the limestone (CaCO3) dissolving the calcite content from the rock and leaving behind small holes and cracks.