The Messenger of Allah ﷺ said, "Any hide that has been tanned is purified."
قال رسول الله ﷺ: أيما إهاب دبغ فقد طهر.
Daraqutni narrated it in Sunan (1/48) and in Ilal (12/365) from Abu Bakr Nisaburi (whose name is Abdullah bin Muhammad bin Ziyad), and Abu Shaykh Asbahani in Tabaqat al-Muhaddithin bi-Asbahan (4/48) from Abdullah bin Husayn bin Zuhayr Nisaburi, both of them from Muhammad bin Aqeel bin Khuwaylid Khuzaee, who said, Hafs bin Abdullah narrated to us, saying, Ibrahim bin Tahman narrated to us, from Ayub, from Nafi, from Ibn Umar, and he related it.Daraqutni said in Sunan, "Its chain of transmission is hasan." And it is as he said, for Ibrahim bin Tahman's hadith is hasan. Ayub here is Ayub Sakhtiyani, and Daraqutni mentioned it in his book al-Gharaib wal-Afrad, as noted in Ibn Qaysarani's Atraf (3241), where he said, "Hafs was alone in narrating it, from Ibrahim bin Tahman, from Ayub." Likewise, Ibn Hajar cited it in Ithaf Mahra (9/29) under the entry for Ayub Sakhtiyani, from Nafi, from Ibn Umar.It has also been said that this is Ayub bin Khawt, who is matruk in hadith, but if this were correct, Daraqutni would not have needed to mention that Ibrahim bin Tahman was alone in narrating from Ayub.