Sahih al-Bukhari, Volume 4, Book 52, Hadith 157 (USC-MSA) ⓘ
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.
حَدَّثَنَا أَحْمَدُ بْنُ مُحَمَّدٍ، أَخْبَرَنَا عَبْدُ اللَّهِ، أَخْبَرَنَا الأَوْزَاعِيُّ، قَالَ سَمِعْتُ سُلَيْمَانَ بْنَ حَبِيبٍ، قَالَ سَمِعْتُ أَبَا أُمَامَةَ، يَقُولُ لَقَدْ فَتَحَ الْفُتُوحَ قَوْمٌ مَا كَانَتْ حِلْيَةُ سُيُوفِهِمِ الذَّهَبَ وَلاَ الْفِضَّةَ، إِنَّمَا كَانَتْ حِلْيَتُهُمُ الْعَلاَبِيَّ وَالآنُكَ وَالْحَدِيدَ.
also referenced under: Book 56, Hadith 122 (In-Book) & Hadith 2909 (DarusSalam)