Not necessarily - may not have an inscription, may need higher magnification to see it (smaller stone w/ thinner girdle)daintyG|1357838442|3352223 said:Not sure if this is what you're looking for, but a diamond certified by GIA will have an inscription you can see with a loupe.
Experience.gregchang35|1357860398|3352563 said:Just another question for this science project... all the above seems to test the diamond/cz when it is a not set ie loose.
what if the diamond or CZ is already set in a ring or earring; how can you distinguish the difference?
denverappraiser|1357855805|3352499 said:Table down, shine a light through the back over a piece of paper a centimeter or so away so the stone acts as a lens. The pattern you see on the paper is quite different.
Grind the subject stone into a fine powder. Burn the powder and examine the flame through your handy UV Spectroscope. Listen carefully to the volume of the screaming from the owner while you do this. High volume means diamond.
Here's a cool test if it's big enough. Hold the stone in between your thumb and first finger and touch it to an ice cube. A diamond will burn through it like a soldering iron. A CZ won't. It's a little hard to do this with stones below about a carat but with a 3 or 4 carater it's a really fun effect.
denverappraiser|1357855805|3352499 said:Grind the subject stone into a fine powder. Burn the powder and examine the flame through your handy UV Spectroscope. Listen carefully to the volume of the screaming from the owner while you do this. High volume means diamond.
stephsaa|1357883065|3352786 said:Thank you all so much for your help. We are going to have a fun weekend. Got a vendor in town to lend me a few large stones and got a few cz's from stullers. I will let you all know how the grade turns out. Teacher emailed me today asking if it was my son or me doing the project. lol... usually the parents endi up doing science class all over again in parenthood!