About Platinum "displacing" when you scratch it, yes, i do mean as opposed to "removing " it. While i definitely dont mean that you will have a whole chunk of gold or other metal falling off, in terms of micro levels, say in terms of the atomic level, Platinum is much more stable than gold, and the atoms just shift their position, without breaking their bonds with each other on the intra-molecular level. Gold, although hard as well, seems to not be as stable as platinum.Their density levels may be very close (Pt=21.45 g/cm cube vs. Au=19.3 g/cm cube) but apparently this is needed for all the difference that God has created them to be.
As for the tarnishing part, yes you are correct that gold will take a long time to tarnish, and that this can be corrected. Platinum too, after a long long time will develop its own patina,(but not becoming blackish like silver)which is also polishable. But Platinum on the other hand is such a highly unreactive metal, that it is virtually unaffected by corrosion due to water, oxygen in the air, and most other chemicals ( strong ones included, now this is the point where gold loses) at even VERY HIGH TEMPERATURE ( where the additional energy helps overcomes the level of entropy thus causing the atoms of said element to react. Gold would react by now). When most other metals would be like melted or damaged heavily, platinum still stands. The only substance that can dissolve platinum is aqua regia, a mixture of concentrated nitric acid & concentrated hydrochloric acid.
It is true that most of the time we watch lovers who are wearing our platinum watches will never find ourselves in a situation where the above characteristics of platinum matters or are utilised, but these are just inherent characteristics of platinum that no other metal can match or even come close to, and if this doesnt matter to most people, thats ok, because im not forcing them to buy platinum watches, i just love it very much myself for everything that platinum is, in terms of chemical properties, and in just owning this most noblest and precious of metals. And if the masses havent spoken their voices, Platinum's popularity would not have soared in the early 1900's, first by Tiffany's of New York, then all the stars and society's elite even decided to go platinum for themselves. Even in the 1800's, Kings, queens,tzars & maharajas have decided to bedeck themselves in platinum,even using platinum thread for their royal gowns[just like i do for my watch straps=) including my CS ] I am in no way affected by this, but i'm just trying to say that these crowds choose platinum over things like the traditional gold, definitely for a reason too.
May i ask then, why is it that if gold in your opinion isnt that far off from platinum, would you recommend someone to buy a platinum watch for keeping a long time, rather than a rodium plated white gold piece?
Hope this helps, and thanks for reading this far!
Stephen