Sunan Ibn Majah, Hadith 3641 ⓘ
It was narrated from Anas bin Malik that the Messenger of Allah wore a ring of silver, in which was an Ethiopian gemstone and the inscription: ‘Muhammad Rasul Allah’ (Muhammad the Messenger of Allah).”
حَدَّثَنَا مُحَمَّدُ بْنُ يَحْيَى، حَدَّثَنَا عُثْمَانُ بْنُ عُمَرَ، حَدَّثَنَا يُونُسُ، عَنِ الزُّهْرِيِّ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ اتَّخَذَ خَاتَمًا مِنْ فِضَّةٍ لَهُ فَصٌّ حَبَشِيٌّ وَنَقْشُهُ مُحَمَّدٌ رَسُولُ اللَّهِ .
also referenced under: Book 32, Hadith 3772 (In-Book) & Volume 4, Book 32, Hadith 3641 (DarusSalam)