Guessing time - what could these be?

[Avondale]

Ok, ok, I know, we don't do identification by photos... but I've seen some people here extract incredible amounts of information from a simple image. So I'm giving it a shot, okay?

Long story short, I was digging through an old and forgotten jewellery box in search of some earrings to wear tonight and came across these ones that belonged to my mother. I was never interested in their gems before, but then we kinda got into a staring contest (in which only I was doing the staring, in case you're thinking I'm crazy) that ended with "they're a bit too different from each other, wonder what they are". So now curiosity is eating at me.

I do not possess the vast knowledge of different types of gems some of you have. I have no idea what these stones could be. I'm pretty sure they're not expensive, or at least weren't expensive at the time they were purchased and worn, which is sometime during the 80s in a then east-of-the-iron-curtain country. The earrings are silver and they're stamped, but the stamp is too worn by now and is illegible.

All guesses are welcome. This is more of a fun subject that I'm just curious about. They're pretty either way and I'm wearing them tonight.



Also, here's a quick video: https://va.media.tumblr.com/tumblr_rdb8qlpbld1zus0r4_720.mp4

 

[stracci2000]

I think either cat's eye quartz or cat's eye chrysoberyl.

 

[LilAlex]

If no chatoyancy -- I can not tell if those are vertical striations in the material vs. play of light -- my vote is some kind of chalcedony like agate.

 

[Daisys and Diamonds]

Ok, ok, I know, we don't do identification by photos... but I've seen some people here extract incredible amounts of information from a simple image. So I'm giving it a shot, okay?

Long story short, I was digging through an old and forgotten jewellery box in search of some earrings to wear tonight and came across these ones that belonged to my mother. I was never interested in their gems before, but then we kinda got into a staring contest (in which only I was doing the staring, in case you're thinking I'm crazy) that ended with "they're a bit too different from each other, wonder what they are". So now curiosity is eating at me.

I do not possess the vast knowledge of different types of gems some of you have. I have no idea what these stones could be. I'm pretty sure they're not expensive, or at least weren't expensive at the time they were purchased and worn, which is sometime during the 80s in a then east-of-the-iron-curtain country. The earrings are silver and they're stamped, but the stamp is too worn by now and is illegible.

All guesses are welcome. This is more of a fun subject that I'm just curious about. They're pretty either way and I'm wearing them tonight.



Also, here's a quick video: https://va.media.tumblr.com/tumblr_rdb8qlpbld1zus0r4_720.mp4

They are very pretty and unusual
If they had been my mother's id be wearing them to lunch or brunch or something nice out

 

[Avondale]

I think either cat's eye quartz or cat's eye chrysoberyl.

Thanks for the suggestions! It definitely looks like some of the cat's eye chrysoberyls I see posted online, but then quartz is so much more common. According to one article the two should be easily distinguished if someone competent can look at them with some basic equipment, so I might take them to get identified at some point.

If no chatoyancy -- I can not tell if those are vertical striations in the material vs. play of light

I have no idea if what they're displaying is chatoyancy. So far I've never been interested in this type of inclusion and figured star and cat's eye gems just aren't my cup of tea, even though so many other people love them. I've only seen what they look like in pictures. And in said pictures the lines are always so straight, thin and well pronounced.

With these two cabs, one of them has a line that's better pronounced. As I rotate it, it kinda moves on the surface left to right. Under a specific angle it almost seems to divide the gem into two different sections, one whiter, and the other looking oddly transparent even though it's not. The other cab does something similar, but the needle isn't straight, it's curved and under some angles it becomes difficult to distinguish.

Don't know if any of this makes sense, but if this is what chatoyancy look like in real life, I'm beginning to understand people's fascination with it. It's mesmerising to watch.

They are very pretty and unusual
If they had been my mother's id be wearing them to lunch or brunch or something nice out

Thank you! I remember when I was a kid I used to really like them, the way the little cabs are held in place by leaves instead of more traditional prongs. The main problem I have with mom's jewellery is that as time went on I developed a taste that's vastly different than hers. Most of her pieces are too "out there" for me to enjoy comfortably. But these particular earrings hit right home.

 

[Starstruck8]

With these two cabs, one of them has a line that's better pronounced. As I rotate it, it kinda moves on the surface left to right. Under a specific angle it almost seems to divide the gem into two different sections, one whiter, and the other looking oddly transparent even though it's not. The other cab does something similar, but the needle isn't straight, it's curved and under some angles it becomes difficult to distinguish.

I'm guessing these are banded agates, cut so that the layers are perpendicular to the surface at about the midline (i.e. if you hold the stone as in your picture and look at it straight on, the edges of the layers are running vertically.) You could check this by looking closely with a loupe.

So when you look straight on at about the midline, you are looking straight into each layer, so you can see deeply into the stone. But if you look at the parts away from the midline, the light leaving the stone is refracted, so you are effectively looking across the layers, hence the opacity. As you turn the stone, you change the position at which you are effectively looking straight into the layers.

To be clear, I'm just making this up - I haven't actually seen agates cut this way. But it seems a plausible story.

Whatever they are, they are absolutely fascinating. Thank you for showing them.

 

[Avondale]

To be clear, I'm just making this up - I haven't actually seen agates cut this way. But it seems a plausible story.

You're very welcome to make all the stuff up - I'm enjoying this immensely and now I had reason to look into agates. Although most seem to be cut in a way that showcases as many "stripes" as possible, I did stumble upon a picture or two that were cut with just two or three layers being displayed.

To be honest, I'm finding it difficult to distinguish layers in these cabs because I don't have a loupe with decent magnification that would allow me to see more clearly.

I also checked youtube for videos of star and cat's eye gems. You'll probably be able to confirm this because judging by your avatar you have at least one such gem - they're not supposed to move, right? In the youtube videos they seemed pretty static on the stone.

So I'm thinking, maybe it's the way light reflects off the surface of the stone that's causing it to look this way. Because this white line is definitely moving, even if you look at it from underneath. This is another quick video: https://va.media.tumblr.com/tumblr_rdd4apo3pL1zus0r4_720.mp4 - the white line is very overexposed which also leads me to believe it's about the way light reflects.

 

[natasha-cupcake]

My first impression was agate. Then I read the comments and looked again. I still think they're probably agate.

 

[stracci2000]

If you've got silky striations that create a moving line, I'd say that's chatoyancy.
They could be lower grade chysoberyls.
Not all gems are cut well and not all stones are so great.....as PSers we sure know that!

I've got some star sapphires with wonky broken stars. They are still amazing in their own way, and the asterism effect is just so interesting.

Here is a good article on cat's eye gems.

Chatoyant Gems: The Mystery of Cat's-Eye Gems Explained

A small number of gemstones have the ability to reflect a sharp line of light known as a cat's-eye that moves just below the surface of the stone as it is turned under a beam of light. This is known as chatoyance. Why does it occur?

geology.com

 

[Gloria27]

Cat's eye Moonstones!

 

[Gloria27]

Could be white cat's eye Silimanite but those usually have a sharper eye. So I think Moonstones is the best bet.

 

[Starstruck8]

To be honest, I'm finding it difficult to distinguish layers in these cabs because I don't have a loupe with decent magnification that would allow me to see more clearly.

I also checked youtube for videos of star and cat's eye gems. You'll probably be able to confirm this because judging by your avatar you have at least one such gem - they're not supposed to move, right? In the youtube videos they seemed pretty static on the stone.

So I'm thinking, maybe it's the way light reflects off the surface of the stone that's causing it to look this way. Because this white line is definitely moving, even if you look at it from underneath. This is another quick video: https://va.media.tumblr.com/tumblr_rdd4apo3pL1zus0r4_720.mp4 - the white line is very overexposed which also leads me to believe it's about the way light reflects.

This is my story in pictures - apologies for the bad drawing and lettering.



If you can't see the layers, that's a problem for my story. Also, your last video makes the stone look more like a true cat's eye. Against that, the curved lines on one of the stones are more consistent with agate.

Could be white cat's eye Silimanite but those usually have a sharper eye. So I think Moonstones is the best bet.

This could be right. I have cat's eye moonstone and sillimanite. In truth, your stone does not really look like either. But some weird sort of moonstone could be a possibility.

I also checked youtube for videos of star and cat's eye gems. You'll probably be able to confirm this because judging by your avatar you have at least one such gem - they're not supposed to move, right? In the youtube videos they seemed pretty static on the stone.

Stars and cat's eyes definitely do move like the lines in your stone, and for the same reason - see the bottom panel of my drawing.

Bottom line: I'm not sure.

 

[Starstruck8]

Further thoughts:

Another possibility: synthetic (= fibre optic glass) cat's eye. These have very bright 'eyes', and come in many colours. I have two similar in size and shape to yours. They are very inexpensive.

In your first picture and video, I wondering whether there may to two sources of light with a gap in the middle (maybe caused by your head or the camera). This could produce the 'two bright line' look with a normal cat's eye.

I'm thinking that the curves lines in the left stone are caused by a flatter (= slightly less curved) area near the top of the dome. (In the video, note how the curve changes as the line passes over the top of the dome.) This could produce curved lines with a normal cat's eye.

A test: shine a torch at the stone (or use direct sun). If you see a single bright line that moves smoothly and doesn't change much in brightness as you turn the stone, you probably have a true cat's eye (natural or synthetic), not an agate like the sort I was suggesting.

I'll be offline for a day or two, so I'll be interested to see how it turns out.

 

[Avondale]

In your first picture and video, I wondering whether there may to two sources of light with a gap in the middle

First picture and video were taken in daylight on a cloudy day on the balcony. So even though the light was mostly coming from one direction, it was more a case of diffused daylight. It's possible I cast a shadow while taking the photo. Second video was taken next to a window with the gem facing the window.

This picture has been taken with a singular source of light, as you suggested. Chatoyancy or not, it can certainly fool you into believing it is one.

I'm thinking that the curves lines in the left stone are caused by a flatter (= slightly less curved) area near the top of the dome.

You are crazy perceptive. The left stone does have flatter areas, it's not cut with a nice rounded dome like the right earring. Not that the cutting on the right is perfect, but it's still better.

Although synthetic is always a possibility I just don't get why anyone would put in the effort to create something with so many imperfections. Especially given the low price of the natural alternatives that have been suggested. Quartz is crazy readily available, agate is cheap as f. Not sure about the price of moonstone, but I'm pretty sure even if we go into considering chrysoberyl as an option, something which is milky/yellowish/brownish and opaque would cost next to nothing.

Back to the subject of agate and layering - I remembered I have this encyclopedia on minerals and gems which has a collection of 80 specimens in boxes, so I dug them out. And I happen to have two agate specimens. One is an agate plate, but the other is blue agate with nicely defined layering - it has a transparent layer and I can see clearly inside of it. Even though the initial picture I posted shows something similar, it's not what you see with the stones in person. Could they still be agate, just not with pronounced layering? After all, agate holds the most votes in this guessing contest for the time being.

 

[Starstruck8]

I’m now pretty sure that your stone is a cat’s eye of some sort (natural or artificial), and that my banded agate story won’t work for it.

Your last picture shows a single bright line (which would be expected for a cat’s eye with a single light source) not bright areas on either side and darker area in the middle (which would be expected on my agate story).

Your first video clearly shows multiple effective light sources. You can see them reflected from the surface of the right stone as it turns. These could well be producing the multiple bright lines.

Here are pics I took of a cat’s eye topaz. Both are were shot in front of a strip of windows. In the left picture, my head blocks the middle (you can see this in the surface reflections) so two bright areas are produced, much as in your first picture. In the right picture, my head is not blocking the light, and there is only a single bright area.



I’m also thinking that your stones are most likely to be fibre optic glass. Here is a picture of one of mine (again, in window light split by my head). See how closely it resembles your stones, right down to the wonky cutting. Here is something you can check: my fibre optic glass cat’s eyes have perfectly flat bases. Every natural cat’s eye stone I have seen has been cut with a curved base.



Here is the sort of thing I had in mind in my agate story. See how the area in the middle is bright while the areas to the left and right are darker (because the camera is looking at the layers edge on). In real life this gives a shimmering ‘watered silk’ look. You could imagine that with the right sort of agate the effect might be stronger. If such an agate were cut with a dome, it would give a moving dark ‘eye’. But, to be clear, that’s just theorizing. I have never actually seen such an agate cut that way.

 

[Daisys and Diamonds]

You know those earings have given us much thought and conversation
They deserve some points for that alone

 

[Avondale]

Here is something you can check: my fibre optic glass cat’s eyes have perfectly flat bases.

Um... bullseye?


Never thought to pay attention to what the back looks like but you're absolutely right - it almost seems as if it was machine cut and then polished and rounded on the face up side only.

Mystery solved! Thank you so much for taking the time to investigate this with me! I have a newly developed appreciation for cat's eye and star inclusions, that's for sure. I never before suspected how fascinating they are to observe and photos definitely don't do them justice.