From Sahih Bukhari (Hadith 6651):
Narrated Ibn `Umar:Allah's Messenger (ﷺ) had a gold ring made for himself, and he used to wear it with the stone towards the inner part of his hand. Consequently, the people had similar rings made for themselves. Afterwards the Prophet; sat on the pulpit and took it off, saying, "I used to wear this ring and keep its stone towards the palm of my hand." He then threw it away and said, "By Allah, I will never wear it." Therefore all the people threw away their rings as well
Reference: Bukhari 6651