What specifications are required for paper in a contract of forward sale?
Chapter on Guaranteed Salaf (Advance Payment) for a Specified Term
Al-Mughni
Book of Sales
Primary text
Paper must be described by its length (ṭūl) and width (ʻarḍ), its thickness (diqqah) and thinness (ghiladh), the evenness of its manufacturing (istiwā' al-ṣan'ah), and any other characteristic that affects its price.