Is the sale involving the pebble (bay' al-hasah) prohibited?
Chapter on Selling the Musarrah (Animal with milk retained in udder)
Al-Mughni
Book of Sales
Primary text
The sale involving the pebble (bay' al-hasah) is prohibited. Abu Hurayrah narrated that the Prophet (peace be upon him) forbade the sale of the pebble, as narrated by Muslim. This prohibition is due to the overwhelming uncertainty (gharar) and ignorance involved in such transactions. There is no known disagreement on this ruling.
Supporting text
The interpretation of the prohibited sale involving the pebble varies. One explanation is when a person says: 'Throw this pebble, and whichever garment it lands upon, it is yours for one dirham.' Another interpretation is when one says: 'I sell you this amount of land, measured by where this pebble lands when you throw it, for a specific price.' A third interpretation is when one says: 'I sell you this item for a specific price, on the condition that if I throw this pebble, the sale becomes obligatory.'