Abu Dawud Book 27, Hadith Number 4036.

Chapter : The view that disapproves of wearing silk.

Narated By Anas ibn Malik : The king of Rome presented a fur of silk brocade to the Prophet (PBUH) and he wore it. The scene that his hands were moving (while wearing the robe) is before my eyes. He then sent it to Ja’far who wore it and came to him. The Prophet (PBUH) said: I did not send it to you to wear. He asked: What should I do with it? He replied: Send it to your brother Negus.