The seal-ring of the Prophet ﷺ was made of silver, and its stone was Abyssinian.
حدثنا قتيبة بن سعيد وأحمد بن صالح قالا حدثنا ابن وهب أخبرني يونس بن يزيد عن ابن شهاب قال
كان خاتم النبي ﷺ من ورق فصه حبشي
Muslim narrated it in "The Book of Clothing," chapter "On the ring of silver with an Abyssinian stone," no. 2094, from the hadith of Ibn Wahb, and Bukhari narrated it in "The Book of Clothing," a chapter after the chapter on the silver ring, no. 5868, from the hadith of Yunus, with the same chain.