I just got a fairly expensive ring from Tiffany & co. And I woke up this morning to find a green ring around my finger under the ring. I thought only cheap jewelry did this. And it’s real sterling silver. So what’s up?I called one of my friends,he told me that”copper sulfate in the band reacting to the oils in your skin, indicating a poor composition of the metal to high copper content, not gold, repair is simple, coat the inside with several layers of clear nail polish, almost certainly guarenteed that its not tiffany, but a knock off made in china or mexico.”is it true?just as my friend said?