(9) باب تَحْرِيمِ بَيْعِ صُبْرَةِ التَّمْرِ الْمَجْهُولَةِ الْقَدْرِ بِتَمْرٍ
Jabir b. Abdullah (Allah be pleased with them) is reported to have said that Allah's Messenger (ﷺ) forbade the sale of a heap of dates the weight of which is unknown in accordance with the known weight of dates.
Reference: Sahih Muslim 1530 a
In-book reference: Book 21, Hadith 50
USC-MSA web (English) reference(deprecated numbering scheme): Book 10, Hadith 3654