Men Wearing Precious Stones and Gems

Islam, the true religion of Allah, encourages Muslims to be neat and tidy. In mosques, Muslims are recommended to wear the most beautiful clothes. Allah says, “O Children of Adam! wear your beautiful apparel at every time and place of prayer…” (Al-Araf: 31)
Coming to the point your raised in your question, it should be clear that diamond, platinum and any precious stones are allowed in Islam for men. However, it is not recommended that they be worn to show arrogance or superiority over others.
Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states: “Men are allowed to wear stones in their rings provided the stones do not fall under the category of unnecessary wastage. This would be the case if a person spends an extravagant amount of money on a stone while his neighbors cannot even have a decent meal. Wastage is forbidden in Islam. The Qur’an characterizes the wasteful as “the friends of Satan” (Al-Isra’: 27).
As for wearing stones as jewellery, it is considered as copying women, which is also forbidden in Islam.
Regarding the question of the stone embedded in the Prophet’s ring, its color is reported to have been black with a streak of white. As mentioned in the sources, the Prophet, peace be on him, wore a ring to serve the purpose of a seal. He did this after being told by his Companions that his letters to the foreign dignitaries would not be honoured unless they were stamped with a seal.
Finally, let me categorically state that considering stones as possessing magical, divining, or protecting properties is blasphemous and rejected outright by the clear teachings of Islam. In Islam, even the most precious of stones, namely the Black Stone (al- hajar al-aswad), has no such significance. The Caliph `Umar, may Allah be pleased with him, wanted to eradicate from the minds of people any trace of such an association when he openly addressed the Black Stone: “I am quite certain that you are only a stone and have no power to benefit or harm. If not for the fact that I saw the Prophet of Allah kissing you, I would not have bothered to do so.”
In the light of the above Fatwa, it becomes crystal clear that all types of jewelry (bracelets, necklaces, etc.) are prohibited for male Muslims except wearing a ring. Jewelry is prohibited because it is considered an ornament, and only women are allowed to have them. The ring that male Muslims are allowed to wear can be made from any material except gold. Therefore, a piece of diamond in a silver ring is allowed. Also, platinum rings are allowed.
Allah Almighty knows best.