Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
ahmad:11452ʿAbd al-Malik b. ʿAmr > Hishām And Yazīd > Hishām > Yaḥyá b. Abū Kathīr > Abū Salamah > Abū Saʿīd al-Khudrī

We were given to eat, during the lifetime of Messenger of Allah ﷺ, dates of different qualities mixed together, and we used to sell two sa's of these for one sa, (of fine quality of dates). This reached Messenger of Allah ﷺ, whereupon he said: There should be no exchange of two sa's of (inferior) dates for one sa (of fine dates) and two sa's of (inferior) wheat for one sa' of (fine) wheat. and one dirham for two dirharms. (Using translation from Muslim 1595)  

أحمد:١١٤٥٢حَدَّثَنَا عَبْدُ الْمَلِكِ بْنُ عَمْرٍو حَدَّثَنَا هِشَامٌ وَيَزِيدُ أَخْبَرَنَا هِشَامٌ عَنْ يَحْيَى بْنِ أَبِي كَثِيرٍ عَنْ أَبِي سَلَمَةَ عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ قَالَ

كُنَّا نُرْزَقُ تَمْرَ الْجَمْعِ عَلَى عَهْدِ رَسُولِ اللهِ ﷺ