Musnad Abu Ya'la al-Mawsili 152:292

Abu Khaythama narrated to us, Affan ibn Muslim narrated to us, Hammad ibn Salama narrated to us, from Asim ibn Bahdala, from Zirr ibn Hubaysh, from Abdullah ibn Mas’ud, regarding this verse: "And he certainly saw him in another descent" (53:13). He said: The Messenger of Allah (peace be upon him) said: "I saw Gabriel at the Lote Tree of the Utmost Boundary. He had six hundred wings. From his feathers, various colors of pearls and rubies were scattering."