turbah

thumb|right|Ayatollah Ali Khamenei prays with a turbah in 2018

A turbah (), or mohr (), also known as khāk-e shefā (, also used in Urdu), sejde gāh (, also used in Urdu) or prayer stone, is a small piece of soil or clay, often a clay tablet, used during salah to symbolize Earth. The use of a turbah is recommended according to the Twelver branch of Shia Islam, a unique practice of the sect, and many ahadith mention the benefits of prostration upon soil or an alternative natural material. The most recommended soil is that of Karbala, the site of the martyrdom of Husayn ibn Ali; however, soil from anywhere may be used. In the absence of soil, plants or items made from these may be substituted. This provision has been extended to include paper.