What is the ruling when a mineral discovered in the land was unknown to the seller at the time of the land sale?
Chapter on Selling Assets and Fruits
Al-Mughni
Book of Sales
Primary text
If a mineral is discovered in the land which the seller was unaware of, the seller has the option to rescind the sale (khayyar). This is because the unknown mineral constitutes an addition (ziyada), analogous to selling a garment stated to be ten units when it is actually eleven. This ruling applies when the seller acquired ownership of the land through revitalization (ihya) or grant (iqta').
Supporting text
If the seller acquired the land through a sale (meaning they were a prior buyer), there is a possibility that they do not have the option, as the right to the hidden mineral belongs to the original owner. Alternatively, they may possess the option, similar to a situation where someone buys a defective item, sells it without knowing the defect, and still maintains the right to return it even after selling it for the same price they bought it for.