What can be the stone with density 6.7

[Alex_Paul]

I would be grateful for the opinions about the gemstone with density (specific gravity) of 6.7 , measured several times. It can be a little bit different with margin of error + - 0.2
First thought it is a cubic zirconia, but on the internet it says cubic zirconia range is 5.7 - 6.0.
The weight of this stone is 1.6 grams or 8 ct. Sorry for the bad pictures, for some reason when using photo flash the stone is not visible. It has the pink color, the blue part is the reflection of computer screen (even though the screen is white). ajsgem.com mentions Cassiterite with such density, but I didn't see pink Cassiterites.

Thanks in advance for your opinions.
Alex

 

[suzanne2]

Hi Alex, spent a while wandering around the specific gravity charts. The usual suspects didn't have pink by any stretch, then I found this:

Apophyllite is a colorless to pink stone with a hardness of only 4½ to 5. .... The high specific gravity, 6.7 to 6.8...

Google was mixing two separate definitions and sent me down a rabbit hole to nowhere. Next, I found this:
http://www.e-gems.cz/en/natural-faceted-gemstones/?cassiterite. There's some red in there...

Finally, my google-fu took me here:
https://www.cs.cmu.edu/~adg/adg-pcassimages.html.
On row 2 there's a thumbnail that could maybe possibly in my dreams yield a small pinkish stone...

At least I've learned A LOT about Cassiterite. So, how about those refractive indexes? Surely you have one right?

"Faceted gems may be brown, yellow or colorless and are pleasing to see. The high specific gravity, 6.7 to 6.8 easily distinguishes it from gems of similar hue. The refractive indices are 1.997 and 2.093."

 

[chatoyancy]

When I want to know about specific gravity, I always go to the gemselect website. They have a cool chart that lists all gemstones in descending order with their specific gravity. It even includes pics next to the stone. It’s how I found the answer to why the heck my 1.06 spessartite garnet looks SO small. Cassiterite is at the top of the list. Also, thegemtrader has so many rare stones. The cassiterite he has on his website now doesn’t look like yours though. That doesn’t mean too much, but I thought I’d check for you. I think you have a pretty stone there!

 

[Alex_Paul]

Thank you for your replies. I found also the gemstone info with very similar density - called cerussite. I think since my density measurements can be off a little bit - it is one of the possibilities. Also cerussite shines very similarly to mine and there are a pink cerussites - please find 2 pictures attached. I think the easy way to differentiate btw 2 of them is cerussite is softer 3 -3.5 on Mohs scale (cassiterite is 6-7). I will try to scratch it a little with the glass.
Alex

 

[T L]

Cerrusite is very diamond like giving off lots of dispersion. Do those gems look like that?

 

[Gloria27]

CZ! Seen this before, google irregular axe fancy cut cubic zirconia and you will find it in any possible colour sold on Ali baba or similar sites.

 

[Alex_Paul]

It is very shining, not sure how it compares to diamonds, but I will try to make day light photos.
I would think it is something less than "light of the dessert" examples from the internet.

 

[Gloria27]

https://www.alibaba.com/showroom/axe-cut-gemstone.html

 

[Alex_Paul]

https://www.alibaba.com/showroom/axe-cut-gemstone.html

Yes, it is true , it is axe cut. What is puzzling is that cerussites and cassiterites have blue and other colors reflections almost "above the surface", and CZ is probably not (more "internal") - attached are pictures of CZ . I use high-precision scales (1/1000 grams), but may be they are off a little.
Thank you,
Alex

 

[Gloria27]

Try to measure the RI, maybe that will give a definitive answer.
Good luck! would be nice to find out it's not a synthetic.

 

[chatoyancy]

Try to measure the RI, maybe that will give a definitive answer.
Good luck! would be nice to find out it's not a synthetic.

OP said the specific gravity of the stone is 6.7, CZ is 5 something.

 

[chatoyancy]

Thank you for your replies. I found also the gemstone info with very similar density - called cerussite. I think since my density measurements can be off a little bit - it is one of the possibilities. Also cerussite shines very similarly to mine and there are a pink cerussites - please find 2 pictures attached. I think the easy way to differentiate btw 2 of them is cerussite is softer 3 -3.5 on Mohs scale (cassiterite is 6-7). I will try to scratch it a little with the glass.
Alex

The top stone looks similar to your stone. There is one on the gem trader.

 

[Gloria27]

OP said the specific gravity of the stone is 6.7, CZ is 5 something.

CZ's SG can be up to 5.9.
the 0.8 difference could be an error

Logic tells me the chances for it to be something else than CZ are low, not impossible but low.
Considering the other options are collectors' gems, and the fancy axe cut which is and was a cut used on commercial grade synthetics for almost two decades now (if I remember well),I'm thinking it would be an odd choice for a cutter to cut a rarer stone like that because it looks like a lot of material gets wasted.

But I could be totally wrong! The above is just my opinion.
I think it would be very cool if it were something else than plain CZ.

 

[chatoyancy]

CZ's SG can be up to 5.9.
the 0.8 difference could be an error

Logic tells me the chances for it to be something else than CZ are low, not impossible but low.
Considering the other options are collectors' gems, and the fancy axe cut which is and was a cut used on commercial grade synthetics for almost two decades now (if I remember well),I'm thinking it would be an odd choice for a cutter to cut a rarer stone like that because it looks like a lot of material gets wasted.

But I could be totally wrong! The above is just my opinion.
I think it would be very cool if it were something else than plain CZ.

I think it would be cool if it were something other than cz too. I always hate it when people have something cool looking and then find out it’s cz.

 

[Alex_Paul]

Just wanted to add day light photos. I was not able to scratch it with the glass, that means it is not cerussite and probably chances of cassiterite are very low . I measured density using 1/1000 (0.001) scales ("smart weigh"), but for some reason 1/100 (0.01) scales I have ("accudigital") show a couple of 1/100 points different weight, just ordered new 1/1000 scales for comparison.
The stone doesn't have black inclusions that are visible on photos , it is some optical effect.
Thank you,
Alex

 

[minousbijoux]

I think its time for you to invest in some decent equipment like a refractometer, and a polariscope rather than to continue to make haphazard guesses based on the responses of an internet forum geared towards consumers. There are online gemology forums for those in the Trade - perhaps you'd have more success there. Just google those three words and one of the first hits should be a major forum for those in the Trade. (We are not allowed to name it here, otherwise I'd provide a link).

 

[Alex_Paul]

I think it is definitely a good advice. I used to collect Russian coins and medals and in that area visual only / photos have been sufficient to differentiate between originals and fakes, no equipment was needed. The same is true , btw, for autographs. The "level of entropy" is equal to zero in those areas (e.g. - my "haphazard guesses" - if the person with sufficient expertise and experience just looked at the photos on the internet. The well-known experts didn't use any equipment, except probably the loupe, in some cases, and their opinion was considered final. For some reason I thought it is applicable in Gemology, but this is not the case. In Gemology the "level of entropy" is very high for "photos only" and equipment is definitely needed.
Alex