posted on February 1, 2001 10:19:00 AM new
How do you tell diamonds from cubic zirconia from plain old glass or rhinestones? Short of taking it to a jeweler and getting it appraised, that is.
I have a piece which I'm not sure about. It looks to be better quality than rhinestones, and I can catch a glimpse of color in there when I turn it at an angle sometimes.
Are there any guidelines for identification of this stuff?
posted on February 1, 2001 10:56:52 AM new
Rainybear, most jewelers can just look at a piece without an appraisal and tell you if it is CZ ,glass or real. I have done it.
posted on February 1, 2001 11:05:24 AM new
I feel like I should be able to look at it myself and tell, but I can't! I'm sure it will turn out to be rhinestones, and then I'll just feel dumb taking it someplace to ask.
If you are ever unsure about something being gold, silver, diamond, etc....
Take it to any pawn shop and ask them what they will give you for it. This will give you an idea (unless its a real crumby pawn shop) as to what its worth. They will test it if they are not sure and this way you will know.
You don't actually have to pawn anything and you don't have to pay them to test it.
posted on February 1, 2001 12:28:09 PM newRainyBear...
Don't feel foolish...even jewelers use special equipment to be sure of a stone. Gemologists go to school for it.
Don't bother if the bottom of the stone is painted...then it's a rhinestone for sure. A real diamond will be set in platinum or gold, unless it's from the 18th or early 19th century...then it might be set in silver.
posted on February 1, 2001 12:30:49 PM new
* * * Diamond is one of the most thermally conductive materials known. That's the basis of the little probe testers you see jewelers use.
You'd be surprised how many jewelers can NOT tell a diamond from a good CZ without this little crutch! As a rule, if you put a diamond next to a good CZ, it's the CZ that most people will think is the diamond!
Rhinestones are glass ("paste". All glass will show little bubbles and swirls, under magnification. And of course glass has nowhere near the refractive index and dispersion ("fire" of either diamond or CZ.
posted on February 1, 2001 01:26:06 PM new
Thanks for the info and advice. I think I just found a couple of chips... which must mean they're rhinestones.
posted on February 1, 2001 01:35:03 PM newRainyBear...
Diamonds can chip. I have a great rose cut diamond, 19th century ring with a little chip. Hurts the value but, if it's a great stone, it can often be recut...
posted on February 1, 2001 05:27:09 PM new
Hey femme!
Oh, yeah, my favorite. The chipped one I mentioned is in a Victorian rose gold solitaire setting...mmm. You need a glass to see the chip...no way am I re-cutting it...
posted on February 1, 2001 06:32:53 PM new
We have a large, and quite prosperous jewelry store here in town. Instead of driving into the next town, which is larger, I had a lose stone in a large new ring and took it into our local jeweler. He asked me where I got it and I told him, at a major wholesale jewelry show. He took one look and informed me the gold wasn't gold, etc. I went home called my Los Angeles jeweler, and started raised heck. THEN, I drove to the next large city, who has a quality jeweler, and had him check it. He informed me our home town jeweler didn't know what he was talking about. The jeweler in the large city tests, it and it came out perfect.
I'll tell you I am VERY careful of where I purchase my jewelry - I don't want one of these uneducated jewelers again.....it is frightening, particularly when you dealing with diamonds,!
posted on February 2, 2001 04:39:46 AM new
RainyBear -- I am a Gemologist and diamond appraiser by trade. Antique and period jewelry is my area of expertise. Most of the information in this thread is correct. You didn't say what period the item appears to be from. In the 1700 to early 1800 period diamonds often had a foilback to help with dispersion as diamond cutting was still quite crude.
I have to agree that not all jewelers have the expertise to distinquish a diamond from a good CZ by sight. They are two completely different materials with different physical properties, therefore the way light behaves within the stone is also different. Without a thermal tester it make take a gemologist to make the distinction.
Thermal testing is not as cut and dried as it used to be with the development and marketing of Synthetic Moissanite. It will test as diamond with a thermal tester. In my opinion CZ looks more like diamond than moissanite, but it sure has put a scare in the secondary market (pawnshops, etc.)
You said that the "diamonds" were chipped.
If you have enough magnification (10 x or more) you should be able to determine diamond by that. Diamond does break but the fracture pattern is in steps. Sort of like broken wood. If the fracture is concoidal ( like a broken pop bottle, in a circular pattern) it is not diamond. Most gemstones have this concoidal pattern, but NOT diamond.
. All glass will show little bubbles and swirls, under magnification. And of course glass has nowhere near the refractive index and dispersion ("fire"