The Prophet ﷺ used to wear the stone of his ring on the inner side of his palm.
حدثنا محمد بن يزيد الواسطي عن عبد الحميد بن جعفر الأنصاري عن نافع
عن النبي ﷺ أنه كان يجعل فص خاتمه مما يلي بطن كفه
Its isnad is sahih. Abdul-Hameed bin Jafar bin Abdullah bin Hakam Ansari, his reliability was already established at 434, and we add here that Ahmad, Ibn Main, and others deemed him reliable, and Ibn Saad said, He was reliable and prolific in hadith. Thawri deemed him daif on account of his views on predestination, but this is no valid reason. The hadith is repeated at 5250, and abridged at 5366.