"Sahih Bukhari, Volume 8, Book 73, Number 182:Narrated Anas bin Malik:Allah's Apostle was on a journey and he had a black slave called Anjasha, and he was driving the camels (very fast, and there were women riding on those camels). Allah's Apostle said, "Waihaka (May Allah be merciful to you), O Anjasha! Drive slowly (the camels) with the glass vessels (women)!""
January 1, 1970
https://en.wikiquote.org/wiki/Medieval_Arab_attitudes_to_Black_people