Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates that Sayyiduna Zayd bin Thabit (may Allah be pleased with him) told him that the Messenger of Allah (peace and blessings be upon him) permitted selling araya for dried dates according to their estimated amount, and did not permit any other form.
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4741