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Help identifying stone


#1

Hi there. I have had this stone for a little over a year now. Since then I have taken to gemologists at high end jewelry stores to be looked at, diamond buyers, and others in the trade and industry to help identify. Apsolutely no one know what stone it is, just that it is a natural stone. I have no way of finding out the RI of this stone and have literally no tools to do so either. My microscope was stolen, so I no longer have this either. I was able to look at through the microscope though a few times. It was difficult to focus because of the odd shape and large size though. It created halos around the stone which hurt my eyes so I didn’t look at it for long.

I have confirmed it does have veil and fingerprint inclusions which are all grouped near the cutlet. There are some in other areas but this cut quite literally makes them disappear and reappear all depending on lighting conditions. It seems they help it reflect light at you because those areas of the stone can blind you when light is directed straight at the table. I posted the photo of this for you to see.

It also has a mirror type effect. At first glance you assume you are seeing through the stone. When examined, you are actually seeing the reflection of you and everything around you. This was confirmed the other day when I finally got a decent photo of my phone light inside the gem stone through the table. It was not even distorted, it was equivalent to a mirror image. at that moment I understood why it was so hard for me to previously capture focused pictures of it with a light source, it was reflecting the light right back at my lens. I posted the photo of this for you to see.

This stone has tested as a diamond before on two different diamond testers. The presidium diamond mate a and also a cheap one from the Internet. It doesn’t do it all the time though, which is also weird. At first I thought maybe it was a colorless sapphire. Then I thought perhaps a colorless tourmaline. I also can’t pin point the specific cut. It’s mixed between a rose cut, briolette and a cushion.

If anyone can shed light on this it would be very helpfull. I’m out of ideas.


#2

More photos


#3

Wanted to show u the effect I get when using a polarized filter with my lens to cancel out the glare. The gemstone literally reflects an exact image of itself back into my lens and then the filter helps to focus it into a mirror image of itself next to it. I can only capture this though when taking a video. I’m assuming this is because it so double refractive.


#4

Maybe try hauling that puppy out of the setting for a specific gravity and hardness test?
Bill Hanneman’s homemade refractometer is simple to make and can read any range of ri. definitely worth a try since you will not be limited by any ri liquid. Cheap too!
Very nice polish.
What does the girdle look like?
Moissanite?


#5

I actually put it in the setting so I could wear it. The specific gravity test is a good idea though. But in order to get a pin point number and not just an idea how would u go about doing that. I know you can weigh it and then weigh it in water and just divide the numbers but isn’t that just a rough idea of what the specific gravity could be? Because the weight of the string etc…


#6

I will loom up the refractometer ur talking about I had no idea about it thank you!!


#7

im just curious it may be kunzite? as a layman technique…if you put kunzite in sunlight it would get a bit darker in few hours…
just try it:)
specific gravity as suggested may give certain answer…


#8

I thought about kunzite also. But kunzite is a beryl and beryl has no thermal conductivity so it wouldn’t make sense for it to have a reaction to the diamond tester, especially testing as a diamond. But I had no idea kunzite got darker in the sunlight that is good information thank you.


#9

It could be moissanite but did not think they made them that big, could it be zircon??? will not get an RI on a normal refractometer if it is

a specific gravity test on a big gem like that would be reasonably accurate normally not so accurate on a gem that is less than a carat as far as I am aware


#10

Getting a reliable SG should be fairly easy with a stone this size. I use an Ainsworth Analytical Balance with a sensitivity of 1/40 of a milligram (0.000025gm). However, you can get a good reading even with a Ohaus Dial-A Gram scale (has a pedestal to support a beaker, etc). I don’t recommend using string. Suggest using a thin bailing wire. String entrains air and will throw your wet weight measurement off…sometimes very significantly. Also, weigh the stone dry both with and without the wire so you know the wire weight. Then when weighing it in distilled water, go in deep enough to just completely submerge the stone. Most of the wire will be out of the water. Subtracting the wire weight from the wet weight will give a closer representation of the stone’s actual wet weight.


#11

This is a wild guess, DR ?. Could it be a Danburite?
RI = 1.6
SG = 3
uV long and short: inert to strong


#12

Hello … Just fact checking here … Kunzite is NOT a Beryl … It if from the Pyroxene Group. True, Kunzite has very little if any thermal-conductivity. False, Kunzite does not get darker when exposed to sunlight … it is the opposite … it is well known to fade in color when exposed to sunlight … so much so that is considered evening jewelry. Michael from The Diamond Grader Lab in Las Vegas. :smiley:


#13

I have two stones that look like that one . Both are around 12 carats. They are untreated Patroke Afghanistan Triphane and the other Hiddenite. When I bought the Hiddenite it was a beautiful green. Then it lost it color and became clear because I was unaware the treatment fades in the sun. I am a very novice collector so I hope this helps


#14

Try it with a Hanneman SG Balance. Excellent and accurate even below the 0.5ct rating.


#15

Mt first guess based on the size and the reading of diamond would be “white sapphire”. Regardless, a beautiful cut and stone. Presidium Duo Tester can get pretty close and just down one tick from diamond is white sapphire. The size says certainly it is not diamond. White sapphire was often used in place as a lower cost alternative to diamond with a much similar appearance. Wish you luck figuring it.


#16

It may be a diaspore
is there any kind of color change in different light sources


#17

Incorrect Shussain, many Kunzites fade upon exposure to sunlight.


#18

Did I write otherwise ?
Yes it will fade. Thanks


#19

You wrote “if you put kunzite in sunlight it would get a bit darker in few hours”