Sunan Abi Dawud, Hadith 4205 ⓘ
Narrated Anas: The signet-ring of the Prophet was all of silver as was also its stone.
حَدَّثَنَا أَحْمَدُ بْنُ يُونُسَ، حَدَّثَنَا زُهَيْرٌ، حَدَّثَنَا حُمَيْدٌ الطَّوِيلُ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ كَانَ خَاتَمُ النَّبِيِّ صلى الله عليه وسلم مِنْ فِضَّةٍ كُلُّهُ فَصُّهُ مِنْهُ .
also referenced under: Hadith 4217 (DarusSalam)