Narrated Abu Umama: Some people conquered many countries and their swords were decorated neither with gold nor silver, but they were decorated with leather, lead and iron.
Hadith Referenceصحيح البخاري / كتاب الجهاد والسير / 2909
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة