4. Ali ibn Ibrahim has narrated from his father from Ibn Abi ‘Umayr from Hammad from al-Halabiy who has said the following: “About the case of a man who buys food from another man, a package by means of known measurement then the party asks the buyer to buy from him another similar package without measurement, because it is similar to the other package already bought. He (the Imam) said, ‘It is not valid without measurement.’ He (the Imam) said, ‘Venturous estimation in food items which are exchanged by measurement is not valid and it is of undesirable matters in food items.’”