Show your Star sapphires and rubies

[Bluegemz]

I've not seen one here though I suspect it's not really sold to the secondary market unless by chance. Now I know if I see 1 I will grab it, regardless of size!

Let us know if you come across any or other unique stars!

 

[Seaglow]

Diffusion requires higher temperatures of 1800C or higher that is close to melting point of sapphire so diffusion rarely works for natural stones, most diffused sapphires are synthetic to produce stars, as the stone has to have high titanium content. You can tell diffused stars because the stars usually occur just at the surface.

The concern on stars is more on glass-filling, which can be done at low temperatures, so glass-filling a stone at low temperature can keep stars in natural corundum when heated in low temperatures that barely alters the silk,

For the transparent synthetic corundum, you can usually tell because they are so clean, highly transparent usually with very distinct thin stars. The combination of high transparency and sharp stars are rare. Remember stars are created by silk, so a super clean, highly transparent star hardly occurs.

White and clear stars with hardly any secondary color is rare. Though there are those that are grayish or bluish which is quite common.

 

[chatoyancy]

This is somewhat hard to describe in words....In my experience, (not an expert) diffusion stars are even, often strong color, (often but not always I imagine) with opacity and a star that appears very surface since the treatment is only on the surface. There is a cotton like, super fine texture to the star as opposed to a more hairlike look of natural stars. With translucent stars that are natural, one can see how the aligned silk penetrates the light deeply into the stone. Ofcourse, It’s harder to tell with natural, more opaque stars. A gem microscope is helpful with this, but as always, if uncertain, send to a lab.

Here are pics of how the asterism channels the light wavelength paths deep within the stone....notice the hair like silk in the asterism, and the graduation of color as the light paths extend through the stone.

Thank you! These examples and your description really help!

 

[chatoyancy]

Here are examples of the surface look of diffusion stars....

This is identical to the diffused star sapphires I saw. Thank you Bluegemz!

 

[chatoyancy]

Here is a lab grown sapphire with diffused star on top. Notice how the star is surface...

The star looks crisp too. Are these called Linde stars?

 

[Bluegemz]

The star looks crisp too. Are these called Linde stars?

No they are lab grown sapphires with the star then diffilused on top with titanium the linde stars look even more fake...powder blues and pinks, mostly opaque and with thin stars.

 

[Bluegemz]

Here’s a Linde Star.....

 

[chatoyancy]

Here’s a Linde Star.....

Thank you. I’ve seen a lot of Linde stars in vintage jewelry. I’m not sure if I’ve seen a lab grown star or not.

 

[Bluegemz]

Thank you. I’ve seen a lot of Linde stars in vintage jewelry. I’m not sure if I’ve seen a lab grown star or not.

Yes these are pretty common from mid century on, trademarked and produced by the Union Carbide company.The other synthetics are likely from different companies, with slightly different manufacturing techniques. All are ‘lab grown’ but linde was the first lab grown star I believe. One article I read mentioned that Linde stars changed the market in that people wanted natural stars to look more like them, which is something hard for me to understand.I think it’s amazing though that people have been able to mimic some of nature’s processes.

 

[Burmesedaze]

If anyone has a few million spare cash lying around... https://carousell.com/p/natural-blu...profile&ref_referrer=/tourlk&ref_sId=12048609

Though honestly, the photos are bad and the cert looks crummy for a US$8.5m stone. Assuming the star sapphire real.

 

[Bluegemz]

If anyone has a few million spare cash lying around... https://carousell.com/p/natural-blue-sapphire-133941447/?ref=profile&ref_referrer=/tourlk&ref_sId=12048609

Though honestly, the photos are bad and the cert looks crummy for a US$8.5m stone. Assuming the star sapphire real.

Wow the size though lol! A small potato!

 

[Burmesedaze]

Wow the size though lol! A small potato!

Lol choker material. Too big and opaque and they lose their ethereal, out-of-this-world look.

 

[Bluegemz]

Lol choker material. Too big and opaque and they lose their ethereal, out-of-this-world look.

Totally agree, though the more opaque ones are great for desk jewelry!

 

[rodentman]

Here ya go:

And from the appraisal:

Approx Measurements: 15.0x12.0x6.7mm
Est weight: 13.02 carats
Tone: Light
Saturation: Slightly greyish
Hue: Violetish Blue
Dome Height: Low
# of Rays: 6
Ray Intensity: Strong
Ray movement: Very good
Phenomena Completeness: Excellent
Transparency: Semi-Transparent
Clarity Notes: Crystal and indented natural present on side of gem

 

[Bluegemz]

Here are some other interesting stars on the carousel....the star earrings are really sweet! Also, I’d love to find a blotchy, pink/white star in better quality sometime. I think a setting with assymetrical rubies and diamonds would be amazing with one of these.

 

[Burmesedaze]

This was posted on Facebook by a Mogok based gem seller yesterday. I see a number of white on white star sapphires. So no. I don't think it's as rare as TGT makes it out to be.

 

[Bluegemz]

This was posted on Facebook by a Mogok based gem seller yesterday. I see a number of white on white star sapphires. So no. I don't think it's as rare as TGT makes it out to be.

All of these whites have secondary colors in them, (except the one at the bottom, front middle) which makes them not as rare. I believe that pure whites are quite rare. I recently found an old one...I’ll try to find a picture.

 

[Burmesedaze]

Let me nose around gem museum tomorrow for the pure whites

 

[Bluegemz]

This one seems quite white, with a just a touch of grey and a nice size at almost 10 carats...not finding a picture of the one which I remembered...oh well.

 

[Bluegemz]

A beautiful, romantic Art Deco Star....such a water color like look...

 

[Burmesedaze]

A beautiful, romantic Art Deco Star....such a water color like look...

Lily pads on water.

 

[Burmesedaze]

The whites

 

[Burmesedaze]

Small peachy orange star

 

[Burmesedaze]

Couple of whites on eBay

https://m.ebay.com/itm/Burma-Myanma...396436?hash=item2f188d9b54:g:iCsAAOSwEOpaGkTZ

https://m.ebay.com/itm/8-48-Carat-H...739433?hash=item3f2e5c4869:g:GygAAOxyNo9SxBJF

 

[mellowyellowgirl]

Did you end up buying anything today @Burmesedaze or you had a looksee?

 

[suzanne2]

Small peachy orange star

Still waiting for my little white to arrive. When it does, I'll post pics. I'm a bit confused as to rarity. @Seaglow thinks they are, and you are having them practically drop out of the sky. Granted, where you live makes a huge difference...Nevertheless, I've really enjoyed you ladies having this nice conversation.

Edited to add: That little peachy star has stolen my heart.

 

[Burmesedaze]

The whites aren't something buyers here care for so they don't stock up on them unless they are already part of a mixed lot.

@mellowyellowgirl the pinks aren't as nice as my pair and the seller wants double the price for them. Back to the negotiating table for the 5ct blue star.

 

[Burmesedaze]

Oh and I kept the peachy
They never come in large sizes here.

They still have boxes and boxes of small star sapphires acquired over 20 years in lots. So I guess there would still be more white ones than the ones I snapped a photo of today. But nothing big, sharp and gemmy.

 

[Bluegemz]

The little peach an unusual color! One of the whites was half clear...that or looks really interesting, like ice mixed with snow.

 

[Burmesedaze]

The Mogok chap has THIS many more cabs in progress!