It was narrated from 'Urwah Al-Bariqi that the Prophet gave rum a Dinar to buy him a sheep, and he bought two sheep for rum, then sold one of them for a Dinar, and brought a Dinar and a sheep to the Prophet. The Messenger of Allah prayed for blessing for him.
He (one of the narrators) said: "If he had bought dust, he would have made a profit from it." (Another chain) from, 'Urwah bin Abu ja'd Al-Bariqi who said: "Some trade arrived, so the Prophet gave me a Dinar." And he mentioned similarly.