This listing is for a set of 18 true Victorian era buttons.  They are metal.  the backs are brass and they are shank style buttons.  I am uncertain of the material that the fronts are made of.  It is a silver color, and not magnetic. The buttons have a 1/2" diameter.  They would be perfect for a Victorian or Edwardian dress or bodice.  Nice to find a set of so many antique buttons still together!