Salam works only with goods whose quality and quantity can be described precisely enough to avoid dispute. Standardized agricultural produce or manufactured goods can often meet this test.
A unique precious stone is different: each stone may vary significantly in quality, size, colour or weight, so an exact future substitute may not be reliably describable. Salam is unsuitable where the promised goods cannot be standardized by specification.
Opening interactive controls...
Advance-Purchase Sale (سَلَم): Why Future Delivery Is Allowed
Salam works only with goods whose quality and quantity can be described precisely enough to avoid dispute. Standardized agricultural produce or manufactured goods can often meet this test.
A unique precious stone is different: each stone may vary significantly in quality, size, colour or weight, so an exact future substitute may not be reliably describable. Salam is unsuitable where the promised goods cannot be standardized by specification.