Tayammum  Tayammum () is the Islamic act of dry Ritual purification using a purified sand or dust, which may be performed in place of ritual washing ("wudu" or "ghusl") if no clean water is readily available or if one is suffering from moisture-induced skin inflammation or scaling. "Tayammum" may be substituted for "wudu" or "ghusl" when access to water is restricted or impractical, namely:   Clarifying the meaning of the verse4:43 O you who have believed, do not approach prayer while you are intoxicated until you know what you are saying or in a state of janabah, except those passing through [a place of prayer], until you have washed [your whole body]. And if you are ill or on a journey or one of you comes from the place of relieving himself or you have contacted women and find no water, then seek clean earth and wipe over your faces and your hands [with it]. Indeed, Allah is ever Pardoning and Forgiving. Thus, in case of illness, even if there is water, one still does not need to wash. The same conditions that invalidate "wudu" also invalidate "tayammum". In addition, a person's "tayammum" is invalidated as and when water becomes available. Tayammum is permitted on  all items which have thick dust on them, baked earthen pots (unglazed), clay, limestone, the ابخش stone, "taahir" (pure) earth, and walls of mud, stone or brick. Tayammum is not permitted on things that are not earthen, such as things that burn and turn into ashes or things that can be melted by heat. Examples include: