Muhammad bin Ziyad (may Allah have mercy on him) said: I heard Sayyiduna Abu Umamah (may Allah be pleased with him) when he was asked about the ornamentation of swords, whether it counts as hoarded treasure. He said: Yes, it is part of hoarded treasure. At this a man said: This is a foolish old man whose mind has gone. So Abu Umamah (may Allah be pleased with him) said: I have only told you what I heard.
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7507