# Separating Diamonds from CZ



## RochelleWest (Dec 3, 2014)

Hello, I have approx 100cts of diamond melee that has some cz mixed in. What is the fastest, easiest way to separate them? I know I could weigh them, but that would take forever. Please help!
Thanks :wink:


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## etack (Dec 3, 2014)

Frosting with HF acid. 

Its dangerous and you should search the forum for info

Hydrofluoric acid

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=39&t=9337

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=49&t=17645

There are more.

Eric


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## RochelleWest (Dec 4, 2014)

etack said:


> Frosting with HF acid.
> 
> Its dangerous and you should search the forum for info
> 
> ...




Thank you for that. I did actually search the forum and found that answer. However, all the responses I found were quite old and I thought I might ask to see if there was anything new and interesting. Is Hydroflouric Acid the same stuff you put on metal that you have cut to look for green foaming to indicate plating? I have some of that. I also have a very well ventilated area. If it is something else, can anyone buy it? If you have a moment to respond to that, thank you so much for your time and knowledge. 8)


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## etack (Dec 4, 2014)

RochelleWest said:


> Is Hydroflouric Acid the same stuff you put on metal that you have cut to look for green foaming to indicate plating?




I'm going to go out on a limb and say if you ask that question STAY away from HF!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

You are referring to nitric acid that you can fall into a vat of and survive (there was a news story about that a few years ago) to an acid they list an antidote to as suggested items to buy with it.

HF will harm you. see if you can find a buyer or refiner to frost your stones for you.

How are you getting the stones? If you are removing them from jewelry and selling the gold the refiner might do it for you at little to no cost.

Be safe.

Eric


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## RochelleWest (Dec 4, 2014)

Yep, that is what I have Nitric Acid. Ok, well I really don't want to own any more toxic chemicals than I already do, so the refiner it is. Thank you so much for the response. I appreciate it very much. Someone should come up with a liquid that is non toxic that would make separation easy. Change their color or something. Someone smart invent that please!


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## Irons (Dec 4, 2014)

There's a quick way that I found many Years ago: Take a sheet of white paper and place the suspect diamonds upside-down on the paper, then look through the stones. The CZ will look like a dilated pupil compared to the Diamonds, which will have reflections throughout.


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## jonn (Dec 4, 2014)

If you take a white piece of paper and put a tiny black pen point on it then put the diamond upside down on the dot you will notice the black dot does not show through with a diamond. 
when you realize what you're looking for you can graduate to a black piece of velvet and do hundreds at a time.


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## justinhcase (Dec 4, 2014)

I would recommend an electronic diamond tester.
Get one of the advanced testers that can differentiate Diamond from Moissanite .
Very fast and simple


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## Irons (Dec 4, 2014)

justinhcase said:


> I would recommend an electronic diamond tester.
> Get one of the advanced testers that can differentiate Diamond from Moissanite .
> Very fast and simple



They do work. I bought one on Fleabay for $18. a few years ago.


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## Anonymous (Dec 5, 2014)

All of the suggestions seem like it will be easier for a person to tell diamonds once they have both a diamond tester, and then the piece of paper and velvet too. I'm sure a jewelers loupe is needed too.

I have some diamonds, but I have to learn more about my readings using my diamond tester. This makes me think about getting some black velvet and also learning about the white piece of paper too. This makes good learning information.

Thanks *jonn* and *Irons* for the info.

Kevin


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## nickvc (Dec 6, 2014)

Testers can and do show white sapphire as diamond but they are heavier than diamond and usually cut differently, the Hf process works great to help identify czs as they become hazy but will leave white sapphire and diamond shiny, remember not all diamond is of great quality so it's the surface that allows identification but it takes experience to pick the diamonds and leave only czs and sapphire behind.
Smoked stones and badly marked stones are easy to miss identify and broken stones can have little value unless large and of good quality.
Welcome to the world of stone dealing its about as easy as understanding the whole of refining and recovery of precious metals but it can add a little to the pot.
While people look only to diamonds for value coloured gems can and do have a value but finding buyers is really hard as that whole world has no written rules or price guides, large,good colour, clear and well cut sapphire, rubies, emeralds etc can and do cost thousands. While small commonly used stones can be cents large good quality stones can be very expensive, high quality sapphire is rising in price monthly and many other stones are doing the same, in truth diamond is common, good quality rare, the same goes for most stones.
Finding good honest buyers is hard but they do exist.


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## Irons (Dec 6, 2014)

Nickvc always gives good advice. He knows the business well, and has educated me more than once.


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