Silver is a chemical element with the symbol Ag (from the Latin argentum, derived from the Proto-Indo-European h₂erǵ: "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite.
You do not need to cover your face for Hijab if the silver stud is not considered by common people in your society as an ornament.
You don't need to remove it during Ehraam unless it is understood as an ornament.
Men are allowed to wear silver but them must avoid wearing what is understood in their society as dress of women.