Ruby information

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Playing with my uv light and thought I would share some information with everyone. What it comes to rubies theres one very easy way to tell if you have a Burmese ruby. All rubies will fluorescence under a uv light but to differentiate the difference between Burmese, a natural ruby from somewhere else and a synthetic ruby you have to look for patterns in the stone and the particular colour it shines.

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As you can see in the above photo the Burmese ruby really glows under the uv light

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Above is a parcel of small rough which has a bonus piece of burmese in the parcel the colour difference is extremely noticeable.

Ill put up some more photos tomorrow sometime showing glass filled and synthetic rubies.
 
I havent forgotten, just cant get the photos that clearly show the differences. I Going to try a couple of different camera setups to hopefully get the shots

The other small rough in the last photo above are from Thailand as well
 
Heres a glass filled ruby at 60x magnification under white and uv light. You can clearly see the air bubbles. I will upload more information as I can get the photos that are clear enough to show the differences

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Also like a heated sapphire you can see the heat lines across the surface of the stone, I forgot to mention its also heated. These types of rubies are created by taking low grade materials then heating and filling the imperfections inside with a lead glass
 
Untreated Ruby lower grade

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Untreated middle grade as you can see theres air pockets in this one but theyre irregular shapes not spherical in shape. Hopefully the photos are nice and clear, damn hard to get a good focus point with all the light

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Can you expand on this? Citations?

Not under standing what creates the 'heat lines'.
 
Interesting, have always kept well away from modified ruby, Sapphire though I believe is far more accepted as heat treated?

Do you know what temp your Sapphire examples were treated to, as I have read that this is fairly critical? From what I gather, rightly or wrongly, a temp of 1750C with a soak and slow cool produces the best results, but not many can afford a furnace that can do this, let alone get their money back on the investment when you add in electricity costs as well. :(

Because of this, heat treatment to lower temperatures is common but produces poorer results??
 
Depends on what you are trying to achieve. Got a list of temps somewhere.
But for composites like those above it can be as low as 900*C

A few ways of detecting heat treatment but I've never heard of 'heat lines'.
 
If I find that Lava plains saph I mentioned in Lefty's (Stones I've cut) which I gave to my daughter (so not holding my breath) I'll try and get some pics.
It was a very ritulated/opaque stone. Sent it up to Sapphire to have it cooked after I cut it (I only did that one pre cut one for heating). Cleared it up immensely. Some rutile left but unfortunately one of the inclusions ruptured near the surface and it ended up with a tiny pit on the table(?) surface that looked like a speck of dust.
There were definitely no lines left after that treatment, which would of been high temp. I don't recall any other evidence of heating that I recall
 
Post #6 My interpretation. Could well be wrong and happy to be proven so. Yes, heat treatment but not for clarity but to add filler and colour.

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Heres a link for more information, Im referring to the information corresponding to page 128. As I have a higher zoom than the photos in the book I think thats where it looks different. I will look again after I get home Monday to verify the treatment for the sapphire I could have mixed up the stone information due to the time I decided to add to the thread the other night when I couldnt sleep. Heres a page wih some more information on heat treating

https://www.gia.edu/doc/Heat-Treating-Ruby-and-Sapphire.pdf
 
Gotcha (I think, at least I hope). And thanks for putting up where you were getting the info from.
An interesting read. In figure 7 I believe the stone on the left has lines because of how the diffusion atom have penetrated the surface layer adding colour, but at facet junctions you're see a double dip on the colour as two surface angles meet. So hence lines.
In the stone on the right of image figure 7 my interpretation (as I read it) is the lines are banding created by different chemical make up as crystal grows. In that stone it looks like it is one side of the crystal.
Yes, they have been heated but that's a secondary thing in these cases.
This is only my thoughts TD.
Also my interpretation of looking for evidence of heating only is heat stress fractures around inclusions, broken rutile needles and chalky looking areas under UV. Two of these I have seen on stone I have had cooked.
I don't know of any others but that's not saying that is it all. .

As a side note any evidence of bubbles round or not is not good. I did google about that and corundum can have bubbles of CO2 but it read as it is fairly unusual. So I would be suspect that all those stones have been filled.

Great photo's too. But I think you may need to try dark field photography for some of these images. I've been trying to get a set up going over the last couple of weeks but not getting the time.
 
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