Musannaf Ibn Abi Shaybah 25585 — Mixing unripe dates, dates

It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that he said: The Messenger of Allah (peace and blessings be upon him) forbade mixing dates and raisins together, and putting semi-ripe and ripe dates together; and he (peace and blessings be upon him) wrote a letter to the people of Jurash in which he (peace and blessings be upon him) forbade them from putting dates and raisins together.