Anas bin Maalik Radiyallahu 'Anhu says that the ring of Rasulullah Sallallahu 'Alayhi Wasallam was ,made of silver and the gem stone was from Abyssinia
Hazrat Ibn Umar radiallahu anhu says that Rasulullah sallallahu alayhe wasallam had a ring made of silver. He used it as a seal (Stamp) on letters etc., but did not wear it
Hazrat Anas radiallahu anhu reports that Rasululah sallallahu alayhe wasallam had a ring made of silver and its (inlaid) gem was also of silver
Anas radiallahu anhu relates:
"When Rasulullah sallallahu alayhe wasallam intended to write letters to the kings of 'Ajam (non arabs), inviting them to Islam, the people said that they did not accept letters without a seal (stamp) on them. Rasulullah sallallahu alayhe wasallam therefore had a ring made, the whiteness of which is still before my eyes.
It is related from Hazrat Anas radiallahu anhu that the inscription engraved on the ring of Rasulullah sallallahu alayhe wasallam was 'Muhammad' on one line, 'Rasul' on a line, and 'Allah' on a line.
Anas Radiyallahu relates that:
Rasulullah sallallahu alayhi wasallam made an intention to write letters to Kisra, Qaysur (Ceasar) and Najashi, inviting them to accept Islaam. The people said: '(O Rasulullah) those people do not accept letters without a stamp on it'. For this reason Rasulullah Sallallahu Alayhi Wasallam had a stamp made. The ring (loop) of which was silver, and had 'Muhammad Rasulullah' engraved on it".
Anas bin Maalik Radiyallahu 'Anhu reports:
"When Rasulullah Sallallahu 'Alayhi Wasallam went to the toilet, he removed his ring"
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"'.