Messenger of Allah ﷺ had a silver ring made for himself and it was worn by him on his hand. Afterwards it was worn by Abu Bakr, and then by ʿUmar, and then by ʿUthman till it fell in the Aris well. (On that ring) was engraved: 'Muhammad, the Messenger of Allah."  

اتَّخَذَ رَسُولُ اللَّهِ ﷺ خَاتَمًا مِنْ وَرِقٍ وَكَانَ فِي يَدِهِ ثُمَّ كَانَ بَعْدُ فِي يَدِ أَبِي بَكْرٍ ثُمَّ كَانَ بَعْدُ فِي يَدِ عُمَرَ ثُمَّ كَانَ بَعْدُ فِي يَدِ عُثْمَانَ حَتَّى وَقَعَ بَعْدُ فِي بِئْرِ أَرِيسَ نَقْشُهُ مُحَمَّدٌ رَسُولُ اللَّهِ  

The Prophet ﷺ got a ring made for himself and said, "I have got a ring made (for myself) and engraved a certain engraving on it so none of you should get such an engraving on his ring." I saw the glitter of the ring on his little finger.  

صَنَعَ النَّبِيُّ ﷺ خَاتَمًا قَالَ إِنَّا اتَّخَذْنَا خَاتَمًا وَنَقَشْنَا فِيهِ نَقْشًا فَلاَ يَنْقُشْ عَلَيْهِ أَحَدٌ قَالَ فَإِنِّي لأَرَى بَرِيقَهُ فِي خِنْصَرِهِ