Markings
Pure, elemental silver is not ferromagnetic. However sterling silver jewelry may be magnetic as a result of the rhodium and nickel plating process or due to the presence of magnetic metals (steel, nickel, iron, cobalt) in the sterling alloy. Sterling silver is 92.5% pure silver with the remaining 7.5% of the alloy traditionally being copper. However, modern alloys may contain different metals that render sterling silver jewelry slightly magnetic.Disclaimer: Sterling Jewelry, Magnetism & Testing
Tests that conclusively verify silver content include the acid/touchstone method (using either aqua regia or Schwerters solution) and XRF analysis.
Magnetism alone is not diagnostic.