Muwatta 1831

Malik says the Messenger forbade muzabana. Its meaning is that any unmeasured guessed item, whose measure, weight or number is not known, is bought for a named measure, weight or number. For example, a man says to a man who has unmeasured food, wheat or dates, or goods of wheat, nuts or pumpkin: sell me all these, or send someone to measure them; whatever falls short of a stated number of sa's, which I name, I will bear the loss until I make up that figure to you, and whatever exceeds that figure is mine. That is not a sale; it is risk, uncertainty and gambling. ¹

Belongs to the Muwatta, Book of Sales. Source: the Muwatta. Mentions Malik ibn Anas. Built on in the chapters on muzabana and uncertainty (gharar).