WHAT is Ruthenium?
Ruthenium, pronounced /ro͞oˈTHēnēəm/ is a chemical element with the symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group.
Ruthenium can be used as a finish for sterling silver jewelry to give it a distinctive light gray through gray black color. It is also the hardest of all the platinum group metals and is a very durable and stable finish.
Ruthenium can prevent scratches and abrasion on the surface, making sterling silver jewelry more durable. With ruthenium plating, surface oxidation can be avoided to a large extent.
Sterling Silver Pieces with Ruthenium Finish by Ketih Jack