This is a beautiful 6 or 8mm Tungsten Carbide Ring with a Black Carbon fiber inlay. Choose from Black Plated or Polished Finish. Cobalt Free. When you're looking for the perfect wedding or anniversary band for yourself or your spouse, this stunning tungsten carbide band is the ideal choice. Whether your spouse works on Wall Street or out in the world with their hands all day, they need a ring that is stylish, durable, and fits their on-the-go lifestyle. That's why we created this gorgeous Tungsten Carbide Wedding Band that has such a clean look. It's scratch resistant, certainly, but it also creates a stunning look that you won't find anywhere else.