What are the conditions for the validity of a Salam contract?

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The Salam contract is only valid if six conditions are met. The first condition is that the commodity being sold (al-muslam fih) must be definable by specifications where price naturally differs based on those specifications. This includes items like grains, fruits, flour, textiles, silk, cotton, linen, wool, hair, paper, iron, lead, brass, copper, medicines, perfumes, vinegar, oils, fats, milk, mercury, alum, sulfur, kohl, and every item that is measured by capacity (kayl), weight (wazn), or is a cultivated crop. Scholarly consensus confirms the permissibility of Salam in foodstuffs and textiles.