Shama-il Tirmidhi Chapter 011, Hadith Number 008 (089).

Ibn 'Umar Radiyallahu 'Anhu says. "Rasulullah Sallallahu 'Alayhi Wasallam kept his ring in his mubaarak hands (possession). Then it was kept by Abubakr Radiyallahu 'Anhu, then by 'Umar Radiyallahu 'Anhu. Thereafter by 'Uthmaan Radiyallahu 'Anhu. In his ('Uthmaan Radiyallahu 'Anhu's) time it fell in the Well of 'Arees. The inscription on this ring was 'Muhammadur Rasulullah"'.

Commentary.
Bir 'Arees is a well near Masjid Quba. During the khilaafah of Sayyidina Uthrnaan Radiyallahu 'Anhu the ring remained with him for six years, then accidently it fell into the well. Sayyidina 'Uthmaan Radiyallahu 'Anhu ordered a thorough search of the well. For two days water of the well was pulled out, but it could not be found. The 'ulama write that from the time the ring fell in the well, mischief and revolt began, and increased in the later years of Sayyidina 'Uthmaan Radiyallahu 'Anhu's khilaafah. In this hadith Sayyidina Ibn 'Umar Radiyallahu 'Anhu says, Sayyidina Rasulullah Sallallahu 'Alayhi Wasallam kept the ring in his mubaarak hands, and in another hadith in this chapter he denies that Sayyidina Rasulullah Sallallahu'Alayhi Wasallam wore a ring. This has already been explained. A special answer to the apparent contradictions in this hadith is that the meaning of Sayyidina Rasuluilah Sallallahu 'Alayhi Wasallam kept the ring in his hands is, he kept it in his possession. It does not necessarily mean that he wore it. It is stated in the following chapter that the ring was kept by Sayyidina Mu'ayqeeb Radiyallahu 'Anhu.