Musnad Ahmad 28:80

Muhammad ibn Ja‘far narrated to us, ‘Awf narrated to us, from Maymun ibn Ustad al-Hazzani, from ‘Abdullah ibn ‘Amr al-Hazzani, from ‘Abdullah ibn ‘Amr ibn al-‘As, from the Messenger of Allah, may Allah bless him and grant him peace, that he said: "Whoever among my nation wears gold, and dies while wearing it, Allah will forbid the gold of Paradise to him. And whoever among my nation wears silk, and dies while wearing it, Allah will forbid the silk of Paradise to him."