Mishkat al-Masabih 3 Purification كتاب الطهارة 200

وَعَنْ سَوْدَةَ زَوْجِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَتْ: مَاتَتْ لَنَا شَاةٌ فَدَبَغْنَا مَسْكَهَا ثُمَّ مَا زِلْنَا نَنْبِذُ فِيهِ حَتَّى صَارَ شنا. رَوَاهُ البُخَارِيّ

Sauda the Prophet’s wife said, “A sheep of ours died and we tanned its freshly flayed skin, then continued to steep dates in it till it was worn out.” Bukhari transmitted it.