"Gold is the most non-reactive of all metals and is benign in all natural and industrial environments.  1) Gold never reacts with oxygen (one of the most active elements), which means it will not rust or tarnish.  2) Gold tarnish is very thin and shows up as a darkening of reflecting surfaces."

Well, excuuuuse me, BUT...if gold will not rust or tarnish, then how can one say that gold tarnish is very thin....yadda, yadda, yadda? 

HA!