Hadith 31-269

وَبِإِسْنادِهِ عَنْ عَلِيِ‏ عَلَيْهِ السَّلامُ قالَ: إِنَّ النَّبِيُ‏ صَلَّى اللهُ عَلَيْهِ وَآلِهِ يَتَخَتَّمُ فِي يَمِينِه.

According to the same documentation, it is narrated that Ali (a.s.) said, “The Prophet (S) wore his ring on his right hand.”