Mishkat al-Masabih
He said the Prophet’s signet-ring was of silver as was also its stone. Bukhari transmitted it.
وَعَنْهُ أَنَّ نَبِيَّ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ كَانَ خَاتَمُهُ مِنْ فِضَّةٍ وَكَانَ فَصُّهُ مِنْهُ. رَوَاهُ البُخَارِيّ
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