"The Messenger of Allah [SAW] wanted to write to the Romans, but they (the Companions) said: 'They do not read any letter unless it has a seal.' So he took a ring of silver, and it is as if I can see its whiteness on his hand, and on it were engraved (the words): "Muhammad Rasul Allah (Muhammad the Messenger of Allah)."
"The Messenger of Allah [SAW] delayed 'Isha' prayer one night, until half the night had passed, then he came out and led us in prayer. And it is as if I can see the whiteness of his silver ring on his hand."
أَخْبَرَنَا عَمْرُو بْنُ عَلِيٍّ، عَنْ أَبِي عَتَّابٍ، سَهْلِ بْنِ حَمَّادٍ ح وَأَنْبَأَنَا أَبُو دَاوُدَ، قَالَ { حَدَّثَنَا سَهْلُ بْنُ حَمَّادٍ، قَالَ } حَدَّثَنَا أَبُو مَكِينٍ، قَالَ حَدَّثَنَا إِيَاسُ بْنُ الْحَارِثِ بْنِ الْمُعَيْقِيبِ، عَنْ جَدِّهِ، مُعَيْقِيبٍ أَنَّهُ قَالَ كَانَ خَاتَمُ النَّبِيِّ صلى الله عليه وسلم حَدِيدًا مَلْوِيًّا عَلَيْهِ فِضَّةٌ - قَالَ - وَرُبَّمَا كَانَ فِي يَدِي . فَكَانَ مُعَيْقِيبٌ عَلَى خَاتَمِ رَسُولِ اللَّهِ صلى الله عليه وسلم .
"The ring of the Prophet [SAW] was made of iron with silver twisted around it." He said: "And sometimes it was on my hand." And Mu'aiqib was the keeper of the ring of the Messenger of Allah [SAW].
"A man came from Al-Bahrain to the Prophet [SAW] and greeted him with Salam, but he did not return his greeting. He was wearing a gold ring on his hand, and was wearing a silken Jubbah. He took them off, then he greeted him with Salam, and he returned his greeting. Then he said: 'O Messenger of Allah, I came to you just now, and you turned away from me.' He said: 'You had a coal of fire on your hand.' He said: 'Then I have brought many coals.' He said: 'What you have brought with you is no better for us than the stones of Al-Harrah, but it is a temporary convenience of this world.' He said: 'What should I use for a ring?' He said: 'A ring of iron or silver or brass.'"
"The Messenger of Allah [SAW] came out wearing a silver ring. He said: 'Whoever wants to make a ring like this, let him do so, but do not put the same inscription.'"
"The Messenger of Allah [SAW] put on a ring, and he had some words inscribed on it. He said: 'We have put on a ring and have had some words engraved on it; no one of you should copy this inscription.'" Then Anas said: "It is as if I can see its whiteness on his hand."
"The Messenger of Allah [SAW] said: 'Do not be so close to the Mushrikin that you can benefit from the light of their fires, and do not engrave Arabic (words) on your rings.'"