Turbah

A turbah (Arabic: تربة, lit. 'soil'), or mohr (Persian: مهر, lit. 'seal'), also known as khāk-e shefā (Persian: خاکِ شِفا, lit. 'medicinal soil', also used in Urdu) and sejde gāh (Persian: سجدہ گاہ, lit. 'place of prostration', also used in Urdu), is a small piece of soil or clay, often a clay tablet, used during salat (Islamic daily prayers) to symbolize earth. The use of a turbah is recommended according to the Twelver Shia school of Islam, a unique practice of the sect, and many Hadiths mention the benefits of prostration (Sajda) upon soil or an alternative natural material. The most favoured 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 plants may be substituted. This provision has been extended to include the use of paper.

Following the instruction from the Quran, Shia Imam Ja'far al-Sadiq stated that "prostration must be performed on pure earth or what grows on it, provided that it is not eaten or worn." For example, prostration on paper is permissible because it is made of natural elements grown on earth.