A: Most likely no, it has not been switched. Diamond-swapping is very uncommon but not unheard of (unfortunately). My grandfather used to say "I've never seen a diamond worth switching." That's because a reputable jeweler knows she or he will have to move the whole family to an island and never be seen again if they try something so horribly stupid. It is more likely that you use well water. Well water contains minerals that affix to diamond and will not come off with anything you have at home. Your jeweler can use a light acid bath commonly called a "pickle" to remove these deposits. You may have to leave it overnight as some of these deposits are stubborn. Pickling twice a year will battle this yellowing and will do no harm to your diamond.
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