أَخْبَرَنَا قُتَيْبَةُ، وَعَلِيُّ بْنُ حُجْرٍ، عَنْ سُفْيَانَ، عَنْ زَيْدِ بْنِ أَسْلَمَ، عَنِ ابْنِ وَعْلَةَ، عَنِ ابْنِ عَبَّاسٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ أَيُّمَا إِهَابٍ دُبِغَ فَقَدْ طَهُرَ ‏"‏ ‏.‏

It was narrated that Ibn 'Abbas said: "The Messenger of Allah said: 'Any skin that is tanned has been purified."' Translation Not Available

Book Ref: Sunan An Nisai Book 41 Hadith 4241
Web Ref:  Sunan An Nisai Vol 5 Book 41 Hadith 4246