Quick question about blue sapphire

[PreRaphaelite]

So let’s say I hypothetically need to determine whether an antique blue sapphire is synthetic. Under 60x, I should look for round growth lines and round or tadpole bubbles, versus what I want to see which is angular growth lines, and irregular inclusions, coupled with weak to moderate magnetic attraction due to iron, and either overall moderate to strong fluorescence, or chalky fluorescence in color-zoned areas correlating to heat treatment (which would not concern me).

Am I way off-base here?

 

[PreRaphaelite]

Anyone?

 

[PreRaphaelite]

Bueller?

 

[PreRaphaelite]

Nobody?

 

[YadaYadaYada]

@Bron357 would be able to help with this, she isn’t in the U.S. so she probably won’t be on until later today.

 

[stracci2000]

Following...........

 

[PreRaphaelite]

Thanks for responding! Please feel free to tag anyone who might know, or even be interested. This is my first foray into sapphire so I’m rarely in the CS section

 

[Roselina]

Following

 

[LilAlex]

Pretty fraught area -- not sure how many folks will be willing to go out on a limb. I don't know anyone who reliably does "home grading" like that especially when the stakes are high (like 100-fold difference in value).

 

[LD]

So let’s say I hypothetically need to determine whether an antique blue sapphire is synthetic. Under 60x, I should look for round growth lines and round or tadpole bubbles, versus what I want to see which is angular growth lines, and irregular inclusions, coupled with weak to moderate magnetic attraction due to iron, and either overall moderate to strong fluorescence, or chalky fluorescence in color-zoned areas correlating to heat treatment (which would not concern me).

Am I way off-base here?

I can only speak from my experience ........... I read tons of books about inclusions, what to look for etc and I've got most tools known to man to distinguish various qualities of a gemstone but would I rely on that? No I wouldn't because some synthetics are so good that only a lab can tell you for sure. If you're looking just for fun to educate yourself then it's a great hobby but if it's to be certain what the gem is, I would suggest sending to a lab.

 

[Bron357]

Reporting for duty.
Synthetic gems are usually identifiable by their “perfection”. Under moderate magnification they show basically nothing. No “bits of stuff”, no colour zoning. Of course a superb natural sapphire can be virtually flawless, it’s uncommon for natural, very common for lab grown.
the main indicator of synthetic is curved striae. That’s basically the growth lines created by the flame fusion process, the boule is grown by layer upon layer of material combining. Can be tricky to see without stronger magnification.
colour zoning is another strong identifying feature of natural. Subtle variations in colour appearing in bands. This is easiest seen in water against a white background. View gem “bottom up”, can be tricky if gem is small and/or set in lots of setting!
So basically, if under magnification you can’t see anything that looks like inclusions or silk or variations of colour it’s much more likely to be synthetic than natural. Then of course you have treatments that usually require more than a loupe to ID.
1. see colour difference at one edge
2. Colour zoning and “bits” heated silk.
3. a feather
4 colour zoning

 

[PreRaphaelite]

Thank you @Bron357 and others who chimed in! This is exactly the confirmation I was looking for. I’ve been reading about diagnostic techniques and I’m eager to get a closer look at the stone - I’ll post pics here ASAP.


Thank you! How exciting!

 

[Rfisher]

I hope you post your adventure as you go about it.
interesting!

 

[MissyBeaucoup]

If you are interested in seeing photos of inclusions under a microscope, there are some beautiful ones at http://www.lotusgemology.com/

There is also a GIA journal online where you can look at back issues. They often address synthetics and various treatments done to gems. It’s all really interesting to learn about.

Watch out, the gem bug will bite you, lol!

 

[Nina-W]

Following

 

[PreRaphaelite]

Under water, white background, bottom of stone:

 

[PreRaphaelite]

Focus, camera!!

 

[PreRaphaelite]

Front view, white background, extreme close up.

 

[PreRaphaelite]

The underside of the stone is oddly-faceted, not symmetrical at all, and not deep-cut really. I’m trying to get pictures but the shank of the ring is in the way. The cutlet is not in the middle, either! An odd stone. Paler on one side too. Hmmmm.

 

[stracci2000]

Front view, white background, extreme close up.

Yup, looks like the real thing to me. Color zoning and silk---yay!

 

[PreRaphaelite]

I will have to do a full post but in the meantime, check out the condition it was in:

 

[stracci2000]

I will have to do a full post but in the meantime, check out the condition it was in:

Yuk!
But the satisfaction you experience after cleaning and polishing this beauty is priceless.
I can't wait till you show us the finished piece so we can ooh and ahh over your restoration!

 

[YadaYadaYada]

 

[Bron357]

Natural, exactly what you would hope to see.

 

[PreRaphaelite]

Natural, exactly what you would hope to see.

@Bron357 I am indebted to you eternally. Thank you so much.

 

[LilAlex]

I will have to do a full post but in the meantime, check out the condition it was in:

I think the most commonly-overlooked "easy fix" for a bezel-set stone is cleaning the back! It's amazing how fast this gets dirty from handwashing, etc.

 

[Polyhex]

What a great and informative post!! Congratulations on your gorgeous natural sapphire find!

 

[Daisys and Diamonds]

I will have to do a full post but in the meantime, check out the condition it was in:

Eww
Its like people not cleaning the inside of their car before they sell it
Thank Goodness she has found a home with you where she will get a regular bath weather she needs it or not !

 

[kenny]

 

[MMtwo]

I will have to do a full post but in the meantime, check out the condition it was in:

Gem abuse. Dear Lord that's filthy! @PreRaphaelite congrats!!!!
@Bron357 thanks so much for the lesson - that was neat.