How do you tell difference between diamond and CZ stud earrings?

I have 2 pairs of earrings - one are CZ and one are diamond (.25 tcw). just by looking at them, how can i tell the difference between them? any ideas?|||1st: Check the mountings, cz's tend to be in cheaper mountings than diamonds.


2nd: Diamonds have flaws. So look for imperfections.


3rd: DIamond mountings tend to have an open bvack to allow light to travel in, while cz mountings tend to be closed back.


4th: Just about ANYTHING will scratch glass. Glass is very weak so don't try the "Diamonds cut/ scratch glass" technique. Its bogus, cz's will do the same thing.|||Diamonds will cut glass CZ won't.|||The easiest way to tell is how clear it is, CZ tend to look cloudy, whereas diamonds are clear.