It is required that the surface used for tayammum be of the same type as the earth, according to the correct opinion: The surface used for tayammum is of two types: the first type is of the same kind as the earth: such as dust, sand, stone, and kohl. This type is permissible for tayammum without dust; because what is considered in tayammum is the contact, as it is obligatory to place the hand on the earth, not to use a part of it, as evidenced by the fact that if one shakes off their hands, the dust on them scatters, how can it scatter without dust? The second type is not of the same kind as the earth: it is everything that burns in fire and turns to ash: such as trees and grass, or that which can be molded and softened: like iron, copper, gold, glass, and similar items, or that which the earth consumes: like wheat, barley, and other grains. This type is not permissible for tayammum without dust, and the evidence for this is the saying of Allah, the Exalted: "So perform tayammum from pure earth," (An-Nisa: 43). The term "pure earth" refers to what appears on the surface of the earth of its kind: such as dust, sand, and stone. And from Hudhayfah, may Allah be pleased with him, he said: The Prophet, peace be upon him, said: "We have been preferred over the people in three ways: our rows have been made like the rows of angels, the entire earth has been made a mosque for us, and its dust has been made pure for us when we do not find water," in Sahih Muslim 1: 371, and Sahih Ibn Hibban 4: 595. And from Abu al-Jahm, may Allah be pleased with him: "The Prophet, peace be upon him, came from the direction of 'Bir Jamal' and met him, but the Prophet did not respond to him until he approached the wall and wiped his face and hands, then he returned the greeting," in Sahih al-Bukhari 1: 129, and Sahih Ibn Khuzaymah 1: 139, and Sahih Ibn Hibban 3: 85. And from Aisha, may Allah be pleased with her: she said: "Whenever the Messenger of Allah, peace be upon him, had relations with one of his family and was too lazy to get up, he would strike his hand on the wall and perform tayammum," in Al-Mu'jam Al-Awsat 1: 202, and Al-Haythami said in Majma' al-Zawa'id 1: 264: And in it is Baqiyyah ibn al-Walid, who is a mudallis. This is supported by what Lady Aisha, may Allah be pleased with her, narrated: "Whenever the Messenger of Allah, peace be upon him, became junub and wanted to sleep, he would perform wudu or tayammum," in Sunan al-Bayhaqi al-Kabir 1: 200, and its chain is good, as in Fath al-Bari. See: I'la al-Sunan 1: 312, Fath Bab al-'Inayah 1: 115, Al-Muhit p. 269, Al-Tabeen 1: 39, and Tuhfat al-Fuqaha 1: 41.