Spark plug used in vehicles contains pure Platinum in the position where it get sparked. Content of Platinum is 0.0001grams in 1pc of Spark plug. (Most of the higher ranged companies like Bosch, NGK, Denso, Champion, Autolite etc…) Some Spark Plugs are single platinum and some even have double coated platinum.
Platinum is even more precious metal when compared to Gold and Silver. Its melting point is 3800F. Platinum-tip center and ground electrode designs for maximum life of a Spark Plug.