Buraidah (may Allah be pleased with him) says that a man came to the Prophet (peace and blessings of Allah be upon him) wearing an iron ring. The Prophet said: "What is the matter? I see that you are wearing the adornment of the people of Hell." Then he came to you wearing a brass ring, and you said: "What is the matter? I smell the odor of idols from you." Then he came to you wearing a gold ring, so you said: "What is the matter? I see that you are wearing the adornment of the people of Paradise." He asked: "What kind of ring should I wear?" You said: "A silver one, and (in weight) keep it less than one mithqal."

Imam Tirmidhi says:
1- This hadith is gharib (strange/rare).
2- There is also a narration on this topic from Abdullah bin Amr.
3- The kunyah of Abdullah bin Muslim is Abu Taybah, and he is Abdullah bin Muslim Marwazi.