In the first place, platinum is used as an inert and durable tip material
in those high quality plugs that carry that designation, not only Bosch does
it but other brands have now picked up on it. The copper mentioned  in spark
plugs is used as a core conductor,  and it is a very good one.  To compare
copper core  plugs with platinum tipped ones is  of no value.  Maybe the
platinum tipped one has a copper core as well.  NGK pioneered the copper
core,  others have now followed suit.  Bosch pioneered the platinum tipped
plug, and the others have followed suit as well.  This so called engineering
explanation that must be written in some  sort of prose   so very obviously
lacks merit that  it is razzel-dazzel in it's purest form.  And to say the
others are pulling our leg in their advertising because they claim platinum
outlasts  iron is crazy.  Who would argue that iron is as durable as
platinum?  Well I suppose the guy that has to  razzel-dazzel   his
explanations.    Platinum plugs last longer, they run cleaner, and the
perform better overall because of these reasons.
   Jeff / Florida

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