Abdullah bin Abi Salamah (may Allah have mercy on him) said: The Messenger of Allah (peace and blessings be upon him) was asked about selling dried dates for fresh dates, and he (peace and blessings be upon him) asked: "Do fresh dates decrease after drying?" The Companions (may Allah be pleased with them) answered: Yes. He (peace and blessings be upon him) said: "Then fresh dates should not be sold for dried ones."
This is a good mursal report, a supporting witness for what preceded.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10564