Musnad Ahmad 33:567

Hassan narrated to us, Ibn Lahi'ah narrated to us, Abu al-Zubayr narrated to us, he said: I asked Jabir about the purple saddle-cloth, and he said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "I do not ride upon it, and I do not wear a shirt hemmed with silk, and I do not wear Qassi (silk-blend) garments."