Language:
كتاب اللباس
77  
Dress
(51)
Chapter: To wear the ring on the little finger
(51)
باب الْخَاتَمِ فِي الْخِنْصَرِ
Sahih al-Bukhari 5874

Narrated Anas:

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.

حَدَّثَنَا أَبُو مَعْمَرٍ، حَدَّثَنَا عَبْدُ الْوَارِثِ، حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ صُهَيْبٍ، عَنْ أَنَسٍ ـ رضى الله عنه ـ قَالَ صَنَعَ النَّبِيُّ صلى الله عليه وسلم خَاتَمًا قَالَ ‏ "‏ إِنَّا اتَّخَذْنَا خَاتَمًا، وَنَقَشْنَا فِيهِ نَقْشًا، فَلاَ يَنْقُشْ عَلَيْهِ أَحَدٌ ‏"‏‏.‏ قَالَ فَإِنِّي لأَرَى بَرِيقَهُ فِي خِنْصَرِهِ‏.‏
Reference : Sahih al-Bukhari 5874
In-book reference : Book 77, Hadith 91
USC-MSA web (English) reference : Vol. 7, Book 72, Hadith 763
  (deprecated numbering scheme)